diff --git a/.gitea/issue_template/enhancement.yaml b/.gitea/issue_template/enhancement.yaml
new file mode 100644
index 0000000..0878f89
--- /dev/null
+++ b/.gitea/issue_template/enhancement.yaml
@@ -0,0 +1,84 @@
+name: Enhancement
+about: Suggest an improvement to an existing feature or functionality
+title: "[Enhancement] "
+labels:
+  - kind/enhancement
+  - status/triage
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to suggest an improvement! This template is for enhancements to **existing** features. If you'd like to request a brand new feature, please use the Feature Request template instead.
+
+  - type: textarea
+    id: current-behavior
+    attributes:
+      label: Current Behavior
+      description: Describe how the existing feature currently works.
+      placeholder: "Currently, when I do X, it works like..."
+    validations:
+      required: true
+
+  - type: textarea
+    id: proposed-improvement
+    attributes:
+      label: Proposed Improvement
+      description: Describe how you'd like the existing feature to be improved.
+      placeholder: "I'd like it to also do Y, or behave differently by..."
+    validations:
+      required: true
+
+  - type: textarea
+    id: use-case
+    attributes:
+      label: Use Case
+      description: Why would this improvement be valuable? What problem does it solve?
+      placeholder: "This would help because..."
+    validations:
+      required: true
+
+  - type: dropdown
+    id: area
+    attributes:
+      label: Area of the Application
+      description: Which part of the application does this enhancement relate to?
+      options:
+        - Dashboard / CVE List
+        - CVE Details
+        - Document Management
+        - User Management
+        - Authentication
+        - Audit Logging
+        - API
+        - Other
+    validations:
+      required: true
+
+  - type: dropdown
+    id: priority
+    attributes:
+      label: Priority
+      description: How important is this enhancement to your workflow?
+      options:
+        - Nice to have
+        - Important
+        - Critical
+    validations:
+      required: true
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternatives or Workarounds
+      description: Are there any current workarounds or alternative approaches you've considered?
+      placeholder: "Currently I work around this by..."
+    validations:
+      required: false
+
+  - type: textarea
+    id: additional-context
+    attributes:
+      label: Additional Context
+      description: Add any other context, screenshots, or mockups about the enhancement here.
+    validations:
+      required: false
diff --git a/backend/.env.example b/backend/.env.example
index 81d2de0..0f61a35 100644
--- a/backend/.env.example
+++ b/backend/.env.example
@@ -2,3 +2,7 @@
 PORT=3001
 API_HOST=localhost
 CORS_ORIGINS=http://localhost:3000
+
+# NVD API Key (optional - increases rate limit from 5 to 50 requests per 30s)
+# Request one at https://nvd.nist.gov/developers/request-an-api-key
+NVD_API_KEY=
diff --git a/backend/routes/nvdLookup.js b/backend/routes/nvdLookup.js
new file mode 100644
index 0000000..c82413f
--- /dev/null
+++ b/backend/routes/nvdLookup.js
@@ -0,0 +1,94 @@
+// NVD CVE Lookup Routes
+const express = require('express');
+
+const CVE_ID_PATTERN = /^CVE-\d{4}-\d{4,}$/;
+
+function createNvdLookupRouter(db, requireAuth) {
+    const router = express.Router();
+
+    // All routes require authentication
+    router.use(requireAuth(db));
+
+    // Lookup CVE details from NVD API 2.0
+    router.get('/lookup/:cveId', async (req, res) => {
+        const { cveId } = req.params;
+
+        if (!CVE_ID_PATTERN.test(cveId)) {
+            return res.status(400).json({ error: 'Invalid CVE ID format. Expected CVE-YYYY-NNNNN.' });
+        }
+
+        const url = `https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=${encodeURIComponent(cveId)}`;
+        const headers = {};
+        if (process.env.NVD_API_KEY) {
+            headers['apiKey'] = process.env.NVD_API_KEY;
+        }
+
+        try {
+            const response = await fetch(url, {
+                headers,
+                signal: AbortSignal.timeout(10000)
+            });
+
+            if (response.status === 404) {
+                return res.status(404).json({ error: 'CVE not found in NVD.' });
+            }
+
+            if (response.status === 429) {
+                return res.status(429).json({ error: 'NVD API rate limit exceeded. Try again later.' });
+            }
+
+            if (!response.ok) {
+                return res.status(502).json({ error: `NVD API returned status ${response.status}.` });
+            }
+
+            const data = await response.json();
+
+            if (!data.vulnerabilities || data.vulnerabilities.length === 0) {
+                return res.status(404).json({ error: 'CVE not found in NVD.' });
+            }
+
+            const vuln = data.vulnerabilities[0].cve;
+
+            // Extract English description
+            const descriptionEntry = vuln.descriptions?.find(d => d.lang === 'en');
+            const description = descriptionEntry ? descriptionEntry.value : '';
+
+            // Extract severity with cascade: CVSS v3.1 → v3.0 → v2.0
+            let severity = null;
+            const metrics = vuln.metrics || {};
+
+            if (metrics.cvssMetricV31 && metrics.cvssMetricV31.length > 0) {
+                severity = metrics.cvssMetricV31[0].cvssData?.baseSeverity;
+            } else if (metrics.cvssMetricV30 && metrics.cvssMetricV30.length > 0) {
+                severity = metrics.cvssMetricV30[0].cvssData?.baseSeverity;
+            } else if (metrics.cvssMetricV2 && metrics.cvssMetricV2.length > 0) {
+                severity = metrics.cvssMetricV2[0].baseSeverity;
+            }
+
+            // Map NVD severity strings to app levels
+            const severityMap = {
+                'CRITICAL': 'Critical',
+                'HIGH': 'High',
+                'MEDIUM': 'Medium',
+                'LOW': 'Low'
+            };
+            severity = severity ? (severityMap[severity.toUpperCase()] || 'Medium') : 'Medium';
+
+            // Extract published date (YYYY-MM-DD)
+            const publishedRaw = vuln.published;
+            const published_date = publishedRaw ? publishedRaw.split('T')[0] : '';
+
+            res.json({ description, severity, published_date });
+        } catch (err) {
+            if (err.name === 'TimeoutError' || err.name === 'AbortError') {
+                return res.status(504).json({ error: 'NVD API request timed out.' });
+            }
+            console.error('NVD lookup error:', err);
+            res.status(502).json({ error: 'Failed to reach NVD API.' });
+        }
+    });
+
+    return router;
+}
+
+module.exports = createNvdLookupRouter;
diff --git a/backend/server.js b/backend/server.js
index 3246bad..d2ede73 100644
--- a/backend/server.js
+++ b/backend/server.js
@@ -17,6 +17,7 @@ const createAuthRouter = require('./routes/auth');
 const createUsersRouter = require('./routes/users');
 const createAuditLogRouter = require('./routes/auditLog');
 const logAudit = require('./helpers/auditLog');
+const createNvdLookupRouter = require('./routes/nvdLookup');
 
 const app = express();
 const PORT = process.env.PORT || 3001;
@@ -56,6 +57,9 @@ app.use('/api/users', createUsersRouter(db, requireAuth, requireRole, logAudit))
 // Audit log routes (admin only)
 app.use('/api/audit-logs', createAuditLogRouter(db, requireAuth, requireRole));
 
+// NVD lookup routes (authenticated users)
+app.use('/api/nvd', createNvdLookupRouter(db, requireAuth));
+
 // Simple storage - upload to temp directory first
 const storage = multer.diskStorage({
     destination: (req, file, cb) => {
@@ -125,6 +129,14 @@ app.get('/api/cves', requireAuth(db), (req, res) => {
     });
 });
 
+// Get distinct CVE IDs for NVD sync (authenticated users)
+app.get('/api/cves/distinct-ids', requireAuth(db), (req, res) => {
+    db.all('SELECT DISTINCT cve_id FROM cves ORDER BY cve_id', [], (err, rows) => {
+        if (err) return res.status(500).json({ error: err.message });
+        res.json(rows.map(r => r.cve_id));
+    });
+});
+
 // Check if CVE exists and get its status - UPDATED FOR MULTI-VENDOR (authenticated users)
 app.get('/api/cves/check/:cveId', requireAuth(db), (req, res) => {
     const { cveId } = req.params;
@@ -262,6 +274,73 @@ app.patch('/api/cves/:cveId/status', requireAuth(db), requireRole('editor', 'adm
     });
 });
 
+// Bulk sync CVE data from NVD (editor or admin)
+app.post('/api/cves/nvd-sync', requireAuth(db), requireRole('editor', 'admin'), (req, res) => {
+    const { updates } = req.body;
+    if (!Array.isArray(updates) || updates.length === 0) {
+        return res.status(400).json({ error: 'No updates provided' });
+    }
+
+    let updated = 0;
+    const errors = [];
+    let completed = 0;
+
+    db.serialize(() => {
+        updates.forEach((entry) => {
+            const fields = [];
+            const values = [];
+            if (entry.description !== null && entry.description !== undefined) {
+                fields.push('description = ?');
+                values.push(entry.description);
+            }
+            if (entry.severity !== null && entry.severity !== undefined) {
+                fields.push('severity = ?');
+                values.push(entry.severity);
+            }
+            if (entry.published_date !== null && entry.published_date !== undefined) {
+                fields.push('published_date = ?');
+                values.push(entry.published_date);
+            }
+            if (fields.length === 0) {
+                completed++;
+                if (completed === updates.length) sendResponse();
+                return;
+            }
+            fields.push('updated_at = CURRENT_TIMESTAMP');
+            values.push(entry.cve_id);
+
+            db.run(
+                `UPDATE cves SET ${fields.join(', ')} WHERE cve_id = ?`,
+                values,
+                function(err) {
+                    if (err) {
+                        errors.push({ cve_id: entry.cve_id, error: err.message });
+                    } else {
+                        updated += this.changes;
+                    }
+                    completed++;
+                    if (completed === updates.length) sendResponse();
+                }
+            );
+        });
+    });
+
+    function sendResponse() {
+        logAudit(db, {
+            userId: req.user.id,
+            username: req.user.username,
+            action: 'cve_nvd_sync',
+            entityType: 'cve',
+            entityId: null,
+            details: { count: updated, cve_ids: updates.map(u => u.cve_id) },
+            ipAddress: req.ip
+        });
+        const result = { message: 'NVD sync completed', updated };
+        if (errors.length > 0) result.errors = errors;
+        res.json(result);
+    }
+});
+
 // ========== DOCUMENT ENDPOINTS ==========
 
 // Get documents for a CVE - FILTER BY VENDOR (authenticated users)
diff --git a/frontend/src/App.js b/frontend/src/App.js
index b7a9f3e..1e0c907 100644
--- a/frontend/src/App.js
+++ b/frontend/src/App.js
@@ -1,10 +1,11 @@
 import React, { useState, useEffect } from 'react';
-import { Search, FileText, AlertCircle, Download, Upload, Eye, Filter, CheckCircle, XCircle, Loader, Trash2, Plus } from 'lucide-react';
+import { Search, FileText, AlertCircle, Download, Upload, Eye, Filter, CheckCircle, XCircle, Loader, Trash2, Plus, RefreshCw } from 'lucide-react';
 import { useAuth } from './contexts/AuthContext';
 import LoginForm from './components/LoginForm';
 import UserMenu from './components/UserMenu';
 import UserManagement from './components/UserManagement';
 import AuditLog from './components/AuditLog';
+import NvdSyncModal from './components/NvdSyncModal';
 
 const API_BASE = process.env.REACT_APP_API_BASE || 'http://localhost:3001/api';
 const API_HOST = process.env.REACT_APP_API_HOST || 'http://localhost:3001';
@@ -29,6 +30,7 @@ export default function App() {
   const [showAddCVE, setShowAddCVE] = useState(false);
   const [showUserManagement, setShowUserManagement] = useState(false);
   const [showAuditLog, setShowAuditLog] = useState(false);
+  const [showNvdSync, setShowNvdSync] = useState(false);
   const [newCVE, setNewCVE] = useState({
     cve_id: '',
     vendor: '',
@@ -37,6 +39,42 @@ export default function App() {
     published_date: new Date().toISOString().split('T')[0]
   });
   const [uploadingFile, setUploadingFile] = useState(false);
+  const [nvdLoading, setNvdLoading] = useState(false);
+  const [nvdError, setNvdError] = useState(null);
+  const [nvdAutoFilled, setNvdAutoFilled] = useState(false);
+
+  const lookupNVD = async (cveId) => {
+    const trimmed = cveId.trim();
+    if (!/^CVE-\d{4}-\d{4,}$/.test(trimmed)) return;
+
+    setNvdLoading(true);
+    setNvdError(null);
+    setNvdAutoFilled(false);
+
+    try {
+      const response = await fetch(`${API_BASE}/nvd/lookup/${encodeURIComponent(trimmed)}`, {
+        credentials: 'include'
+      });
+
+      if (!response.ok) {
+        const data = await response.json();
+        throw new Error(data.error || 'NVD lookup failed');
+      }
+
+      const data = await response.json();
+      setNewCVE(prev => ({
+        ...prev,
+        description: prev.description || data.description,
+        severity: data.severity,
+        published_date: data.published_date || prev.published_date
+      }));
+      setNvdAutoFilled(true);
+    } catch (err) {
+      setNvdError(err.message);
+    } finally {
+      setNvdLoading(false);
+    }
+  };
 
   const fetchCVEs = async () => {
     setLoading(true);
@@ -163,6 +201,9 @@ export default function App() {
         description: '',
         published_date: new Date().toISOString().split('T')[0]
       });
+      setNvdLoading(false);
+      setNvdError(null);
+      setNvdAutoFilled(false);
       fetchCVEs();
     } catch (err) {
       alert(`Error: ${err.message}`);
@@ -297,6 +338,15 @@ export default function App() {
             <p className="text-gray-600">Query vulnerabilities, manage vendors, and attach documentation</p>
           </div>
           <div className="flex items-center gap-4">
+            {canWrite() && (
+              <button
+                onClick={() => setShowNvdSync(true)}
+                className="px-4 py-2 bg-green-600 text-white rounded-lg hover:bg-green-700 transition-colors flex items-center gap-2 shadow-md"
+              >
+                <RefreshCw className="w-5 h-5" />
+                Sync with NVD
+              </button>
+            )}
             {canWrite() && (
               <button
                 onClick={() => setShowAddCVE(true)}
@@ -320,6 +370,11 @@ export default function App() {
           <AuditLog onClose={() => setShowAuditLog(false)} />
         )}
 
+        {/* NVD Sync Modal */}
+        {showNvdSync && (
+          <NvdSyncModal onClose={() => setShowNvdSync(false)} onSyncComplete={() => fetchCVEs()} />
+        )}
+
         {/* Add CVE Modal */}
         {showAddCVE && (
           <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50 p-4">
@@ -328,7 +383,7 @@ export default function App() {
                 <div className="flex justify-between items-center mb-4">
                   <h2 className="text-2xl font-bold text-gray-900">Add CVE Entry</h2>
                   <button
-                    onClick={() => setShowAddCVE(false)}
+                    onClick={() => { setShowAddCVE(false); setNvdLoading(false); setNvdError(null); setNvdAutoFilled(false); }}
                     className="text-gray-400 hover:text-gray-600"
                   >
                     <XCircle className="w-6 h-6" />
@@ -347,15 +402,33 @@ export default function App() {
                     <label className="block text-sm font-medium text-gray-700 mb-1">
                       CVE ID *
                     </label>
-                    <input
-                      type="text"
-                      required
-                      placeholder="CVE-2024-1234"
-                      value={newCVE.cve_id}
-                      onChange={(e) => setNewCVE({...newCVE, cve_id: e.target.value.toUpperCase()})}
-                      className="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-[#0476D9] focus:border-transparent"
-                    />
+                    <div className="relative">
+                      <input
+                        type="text"
+                        required
+                        placeholder="CVE-2024-1234"
+                        value={newCVE.cve_id}
+                        onChange={(e) => { setNewCVE({...newCVE, cve_id: e.target.value.toUpperCase()}); setNvdAutoFilled(false); setNvdError(null); }}
+                        onBlur={(e) => lookupNVD(e.target.value)}
+                        className="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-[#0476D9] focus:border-transparent"
+                      />
+                      {nvdLoading && (
+                        <Loader className="absolute right-3 top-2.5 w-5 h-5 text-[#0476D9] animate-spin" />
+                      )}
+                    </div>
                     <p className="text-xs text-gray-500 mt-1">Can be the same as existing CVE if adding another vendor</p>
+                    {nvdAutoFilled && (
+                      <p className="text-xs text-green-600 mt-1 flex items-center gap-1">
+                        <CheckCircle className="w-3 h-3" />
+                        Auto-filled from NVD
+                      </p>
+                    )}
+                    {nvdError && (
+                      <p className="text-xs text-amber-600 mt-1 flex items-center gap-1">
+                        <AlertCircle className="w-3 h-3" />
+                        {nvdError}
+                      </p>
+                    )}
                   </div>
                   
                   <div>
@@ -425,7 +498,7 @@ export default function App() {
                     </button>
                     <button
                       type="button"
-                      onClick={() => setShowAddCVE(false)}
+                      onClick={() => { setShowAddCVE(false); setNvdLoading(false); setNvdError(null); setNvdAutoFilled(false); }}
                       className="px-4 py-2 bg-gray-200 text-gray-700 rounded-lg hover:bg-gray-300 transition-colors"
                     >
                       Cancel
diff --git a/frontend/src/components/AuditLog.js b/frontend/src/components/AuditLog.js
index 4f8f084..bdea872 100644
--- a/frontend/src/components/AuditLog.js
+++ b/frontend/src/components/AuditLog.js
@@ -14,6 +14,7 @@ const ACTION_BADGES = {
     user_create:        { bg: 'bg-blue-100',   text: 'text-blue-800' },
     user_update:        { bg: 'bg-yellow-100', text: 'text-yellow-800' },
     user_delete:        { bg: 'bg-red-100',    text: 'text-red-800' },
+    cve_nvd_sync:       { bg: 'bg-green-100',  text: 'text-green-800' },
 };
 
 const ENTITY_TYPES = ['auth', 'cve', 'document', 'user'];
diff --git a/frontend/src/components/NvdSyncModal.js b/frontend/src/components/NvdSyncModal.js
new file mode 100644
index 0000000..448cecf
--- /dev/null
+++ b/frontend/src/components/NvdSyncModal.js
@@ -0,0 +1,509 @@
+import React, { useState, useEffect, useRef } from 'react';
+import { X, Loader, AlertCircle, CheckCircle, RefreshCw, ChevronDown, ChevronUp } from 'lucide-react';
+
+const API_BASE = process.env.REACT_APP_API_BASE || 'http://localhost:3001/api';
+
+const FETCH_DELAY_MS = 7000; // 7 seconds between requests (safe for 5 req/30s without API key)
+const RETRY_DELAY_MS = 35000; // Wait 35 seconds on 429 before retry
+
+export default function NvdSyncModal({ onClose, onSyncComplete }) {
+  const [phase, setPhase] = useState('idle'); // idle, fetching, review, applying, done
+  const [cveIds, setCveIds] = useState([]);
+  const [fetchProgress, setFetchProgress] = useState({ current: 0, total: 0, currentId: '' });
+  const [results, setResults] = useState({}); // { cveId: { nvd: {...}, current: {...}, status: 'found'|'not_found'|'error'|'no_change', error: '' } }
+  const [descriptionChoices, setDescriptionChoices] = useState({}); // { cveId: 'keep' | 'nvd' }
+  const [applyResult, setApplyResult] = useState(null);
+  const [expandedDesc, setExpandedDesc] = useState({});
+  const abortRef = useRef(null);
+
+  // Fetch distinct CVE IDs on mount
+  useEffect(() => {
+    (async () => {
+      try {
+        const response = await fetch(`${API_BASE}/cves/distinct-ids`, { credentials: 'include' });
+        if (!response.ok) throw new Error('Failed to fetch CVE list');
+        const data = await response.json();
+        setCveIds(data);
+      } catch (err) {
+        console.error('Error fetching CVE IDs:', err);
+      }
+    })();
+  }, []);
+
+  const sleep = (ms) => new Promise(resolve => setTimeout(resolve, ms));
+
+  const fetchNvdData = async () => {
+    setPhase('fetching');
+    const controller = new AbortController();
+    abortRef.current = controller;
+    const newResults = {};
+    setFetchProgress({ current: 0, total: cveIds.length, currentId: '' });
+
+    // First fetch current data for all CVEs
+    let currentData = {};
+    try {
+      const response = await fetch(`${API_BASE}/cves`, { credentials: 'include', signal: controller.signal });
+      if (response.ok) {
+        const allCves = await response.json();
+        // Group by cve_id, take first entry for description/severity/date
+        allCves.forEach(cve => {
+          if (!currentData[cve.cve_id]) {
+            currentData[cve.cve_id] = {
+              description: cve.description,
+              severity: cve.severity,
+              published_date: cve.published_date
+            };
+          }
+        });
+      }
+    } catch (err) {
+      if (err.name === 'AbortError') { setPhase('idle'); return; }
+    }
+
+    for (let i = 0; i < cveIds.length; i++) {
+      if (controller.signal.aborted) break;
+
+      const cveId = cveIds[i];
+      setFetchProgress({ current: i + 1, total: cveIds.length, currentId: cveId });
+
+      try {
+        let response = await fetch(`${API_BASE}/nvd/lookup/${encodeURIComponent(cveId)}`, {
+          credentials: 'include',
+          signal: controller.signal
+        });
+
+        // Handle rate limit with one retry
+        if (response.status === 429) {
+          await sleep(RETRY_DELAY_MS);
+          if (controller.signal.aborted) break;
+          response = await fetch(`${API_BASE}/nvd/lookup/${encodeURIComponent(cveId)}`, {
+            credentials: 'include',
+            signal: controller.signal
+          });
+        }
+
+        if (response.status === 404) {
+          newResults[cveId] = { status: 'not_found', current: currentData[cveId] || {} };
+        } else if (!response.ok) {
+          const data = await response.json().catch(() => ({}));
+          newResults[cveId] = { status: 'error', error: data.error || `HTTP ${response.status}`, current: currentData[cveId] || {} };
+        } else {
+          const nvd = await response.json();
+          const current = currentData[cveId] || {};
+
+          const descChanged = nvd.description && nvd.description !== current.description;
+          const sevChanged = nvd.severity && nvd.severity !== current.severity;
+          const dateChanged = nvd.published_date && nvd.published_date !== current.published_date;
+
+          if (!descChanged && !sevChanged && !dateChanged) {
+            newResults[cveId] = { status: 'no_change', nvd, current };
+          } else {
+            newResults[cveId] = { status: 'found', nvd, current, descChanged, sevChanged, dateChanged };
+          }
+        }
+      } catch (err) {
+        if (err.name === 'AbortError') break;
+        newResults[cveId] = { status: 'error', error: err.message, current: currentData[cveId] || {} };
+      }
+
+      // Update results progressively
+      setResults({ ...newResults });
+
+      // Rate limit delay (skip after last item)
+      if (i < cveIds.length - 1 && !controller.signal.aborted) {
+        await sleep(FETCH_DELAY_MS);
+      }
+    }
+
+    if (!controller.signal.aborted) {
+      setResults({ ...newResults });
+      // Default all description choices to 'keep'
+      const choices = {};
+      Object.entries(newResults).forEach(([id, r]) => {
+        if (r.status === 'found' && r.descChanged) {
+          choices[id] = 'keep';
+        }
+      });
+      setDescriptionChoices(choices);
+      setPhase('review');
+    }
+  };
+
+  const cancelFetch = () => {
+    if (abortRef.current) abortRef.current.abort();
+    setPhase('idle');
+  };
+
+  const setBulkDescriptionChoice = (choice) => {
+    const newChoices = {};
+    Object.keys(descriptionChoices).forEach(id => {
+      newChoices[id] = choice;
+    });
+    setDescriptionChoices(newChoices);
+  };
+
+  const getChangesCount = () => {
+    let count = 0;
+    Object.entries(results).forEach(([id, r]) => {
+      if (r.status === 'found') {
+        if (r.sevChanged || r.dateChanged || (r.descChanged && descriptionChoices[id] === 'nvd')) {
+          count++;
+        }
+      }
+    });
+    return count;
+  };
+
+  const applyChanges = async () => {
+    setPhase('applying');
+    const updates = [];
+
+    Object.entries(results).forEach(([cveId, r]) => {
+      if (r.status !== 'found') return;
+
+      const update = { cve_id: cveId };
+      let hasChange = false;
+
+      if (r.sevChanged) {
+        update.severity = r.nvd.severity;
+        hasChange = true;
+      }
+      if (r.dateChanged) {
+        update.published_date = r.nvd.published_date;
+        hasChange = true;
+      }
+      if (r.descChanged && descriptionChoices[cveId] === 'nvd') {
+        update.description = r.nvd.description;
+        hasChange = true;
+      }
+
+      if (hasChange) updates.push(update);
+    });
+
+    if (updates.length === 0) {
+      setApplyResult({ updated: 0, message: 'No changes to apply' });
+      setPhase('done');
+      return;
+    }
+
+    try {
+      const response = await fetch(`${API_BASE}/cves/nvd-sync`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        credentials: 'include',
+        body: JSON.stringify({ updates })
+      });
+
+      if (!response.ok) {
+        const data = await response.json().catch(() => ({}));
+        throw new Error(data.error || 'Sync failed');
+      }
+
+      const data = await response.json();
+      setApplyResult(data);
+      onSyncComplete();
+    } catch (err) {
+      setApplyResult({ error: err.message });
+    }
+    setPhase('done');
+  };
+
+  const truncate = (str, len = 120) => str && str.length > len ? str.substring(0, len) + '...' : str;
+
+  // Summary counts
+  const foundCount = Object.values(results).filter(r => r.status === 'found').length;
+  const noChangeCount = Object.values(results).filter(r => r.status === 'no_change').length;
+  const notFoundCount = Object.values(results).filter(r => r.status === 'not_found').length;
+  const errorCount = Object.values(results).filter(r => r.status === 'error').length;
+
+  return (
+    <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50 p-4">
+      <div className="bg-white rounded-lg shadow-xl max-w-5xl w-full max-h-[90vh] flex flex-col">
+        {/* Header */}
+        <div className="p-6 border-b border-gray-200 flex justify-between items-center flex-shrink-0">
+          <div>
+            <h2 className="text-2xl font-bold text-gray-900 flex items-center gap-2">
+              <RefreshCw className="w-6 h-6 text-green-600" />
+              Sync with NVD
+            </h2>
+            <p className="text-sm text-gray-500 mt-1">Update existing CVE entries with data from the National Vulnerability Database</p>
+          </div>
+          <button onClick={onClose} className="text-gray-400 hover:text-gray-600">
+            <X className="w-6 h-6" />
+          </button>
+        </div>
+
+        {/* Body */}
+        <div className="p-6 overflow-y-auto flex-1">
+          {/* Idle Phase */}
+          {phase === 'idle' && (
+            <div className="text-center py-8">
+              <p className="text-lg text-gray-700 mb-2">
+                {cveIds.length > 0
+                  ? <><strong>{cveIds.length}</strong> unique CVE{cveIds.length !== 1 ? 's' : ''} in database</>
+                  : 'Loading CVE count...'}
+              </p>
+              <p className="text-sm text-gray-500 mb-6">
+                This will fetch data from NVD for each CVE and let you review changes before applying.
+                Rate-limited to stay within NVD API limits.
+              </p>
+              <button
+                onClick={fetchNvdData}
+                disabled={cveIds.length === 0}
+                className="px-6 py-3 bg-green-600 text-white rounded-lg hover:bg-green-700 transition-colors font-medium shadow-md disabled:opacity-50 flex items-center gap-2 mx-auto"
+              >
+                <RefreshCw className="w-5 h-5" />
+                Fetch NVD Data
+              </button>
+            </div>
+          )}
+
+          {/* Fetching Phase */}
+          {phase === 'fetching' && (
+            <div className="py-8">
+              <div className="text-center mb-6">
+                <Loader className="w-8 h-8 text-green-600 animate-spin mx-auto mb-3" />
+                <p className="text-lg text-gray-700">
+                  Fetching CVE {fetchProgress.current} of {fetchProgress.total}
+                </p>
+                <p className="text-sm text-gray-500 font-mono mt-1">{fetchProgress.currentId}</p>
+              </div>
+              {/* Progress bar */}
+              <div className="w-full bg-gray-200 rounded-full h-3 mb-4">
+                <div
+                  className="bg-green-600 h-3 rounded-full transition-all duration-300"
+                  style={{ width: `${fetchProgress.total > 0 ? (fetchProgress.current / fetchProgress.total) * 100 : 0}%` }}
+                />
+              </div>
+              <div className="text-center">
+                <button
+                  onClick={cancelFetch}
+                  className="px-4 py-2 bg-gray-200 text-gray-700 rounded-lg hover:bg-gray-300 transition-colors"
+                >
+                  Cancel
+                </button>
+              </div>
+            </div>
+          )}
+
+          {/* Review Phase */}
+          {phase === 'review' && (
+            <div>
+              {/* Summary bar */}
+              <div className="flex flex-wrap gap-3 mb-4 p-3 bg-gray-50 rounded-lg text-sm">
+                <span className="font-medium">Found: <span className="text-green-700">{foundCount}</span></span>
+                <span>|</span>
+                <span>Up to date: <span className="text-gray-600">{noChangeCount}</span></span>
+                <span>|</span>
+                <span>Changes: <span className="text-blue-700">{foundCount}</span></span>
+                <span>|</span>
+                <span>Not in NVD: <span className="text-gray-400">{notFoundCount}</span></span>
+                <span>|</span>
+                <span>Errors: <span className="text-red-600">{errorCount}</span></span>
+              </div>
+
+              {/* Bulk controls */}
+              {Object.keys(descriptionChoices).length > 0 && (
+                <div className="flex gap-2 mb-4">
+                  <span className="text-sm text-gray-600 self-center">Descriptions:</span>
+                  <button
+                    onClick={() => setBulkDescriptionChoice('keep')}
+                    className="px-3 py-1 text-xs rounded border border-gray-300 hover:bg-gray-100 transition-colors"
+                  >
+                    Keep All Existing
+                  </button>
+                  <button
+                    onClick={() => setBulkDescriptionChoice('nvd')}
+                    className="px-3 py-1 text-xs rounded border border-green-300 text-green-700 hover:bg-green-50 transition-colors"
+                  >
+                    Use All NVD
+                  </button>
+                </div>
+              )}
+
+              {/* Comparison table */}
+              <div className="space-y-2">
+                {Object.entries(results).map(([cveId, r]) => {
+                  if (r.status === 'no_change') {
+                    return (
+                      <div key={cveId} className="flex items-center gap-3 p-3 bg-gray-50 rounded-lg text-sm">
+                        <span className="text-gray-400">—</span>
+                        <span className="font-mono font-medium text-gray-500">{cveId}</span>
+                        <span className="text-gray-400">No changes needed</span>
+                      </div>
+                    );
+                  }
+
+                  if (r.status === 'not_found') {
+                    return (
+                      <div key={cveId} className="flex items-center gap-3 p-3 bg-gray-50 rounded-lg text-sm">
+                        <span className="text-gray-400">—</span>
+                        <span className="font-mono font-medium text-gray-400">{cveId}</span>
+                        <span className="text-gray-400 italic">Not found in NVD</span>
+                      </div>
+                    );
+                  }
+
+                  if (r.status === 'error') {
+                    return (
+                      <div key={cveId} className="flex items-center gap-3 p-3 bg-red-50 rounded-lg text-sm">
+                        <AlertCircle className="w-4 h-4 text-red-500 flex-shrink-0" />
+                        <span className="font-mono font-medium text-gray-700">{cveId}</span>
+                        <span className="text-red-600">{r.error}</span>
+                      </div>
+                    );
+                  }
+
+                  // status === 'found' — show changes
+                  const isExpanded = expandedDesc[cveId];
+                  return (
+                    <div key={cveId} className="border border-gray-200 rounded-lg p-4 bg-white">
+                      <div className="flex items-start gap-3">
+                        <CheckCircle className="w-4 h-4 text-green-500 mt-1 flex-shrink-0" />
+                        <div className="flex-1 min-w-0">
+                          <div className="flex items-center gap-3 mb-2 flex-wrap">
+                            <span className="font-mono font-bold text-gray-900">{cveId}</span>
+                            {r.sevChanged && (
+                              <span className="text-xs">
+                                Severity: <span className="text-red-600">{r.current.severity}</span>
+                                {' → '}
+                                <span className="text-green-700">{r.nvd.severity}</span>
+                              </span>
+                            )}
+                            {r.dateChanged && (
+                              <span className="text-xs">
+                                Date: <span className="text-red-600">{r.current.published_date || '(none)'}</span>
+                                {' → '}
+                                <span className="text-green-700">{r.nvd.published_date}</span>
+                              </span>
+                            )}
+                          </div>
+
+                          {r.descChanged && (
+                            <div className="mt-2">
+                              <div className="flex items-center gap-2 mb-2">
+                                <span className="text-xs font-medium text-gray-600">Description:</span>
+                                <button
+                                  onClick={() => setExpandedDesc(prev => ({ ...prev, [cveId]: !prev[cveId] }))}
+                                  className="text-xs text-blue-600 hover:text-blue-800 flex items-center gap-1"
+                                >
+                                  {isExpanded ? <ChevronUp className="w-3 h-3" /> : <ChevronDown className="w-3 h-3" />}
+                                  {isExpanded ? 'Collapse' : 'Expand'}
+                                </button>
+                              </div>
+                              {isExpanded ? (
+                                <div className="space-y-2 text-xs">
+                                  <div className="p-2 bg-red-50 rounded border border-red-200">
+                                    <span className="font-medium text-red-700">Current: </span>
+                                    <span className="text-gray-700">{r.current.description || '(empty)'}</span>
+                                  </div>
+                                  <div className="p-2 bg-green-50 rounded border border-green-200">
+                                    <span className="font-medium text-green-700">NVD: </span>
+                                    <span className="text-gray-700">{r.nvd.description}</span>
+                                  </div>
+                                </div>
+                              ) : (
+                                <p className="text-xs text-gray-500">{truncate(r.nvd.description)}</p>
+                              )}
+
+                              {/* Description choice */}
+                              <div className="flex gap-4 mt-2">
+                                <label className="flex items-center gap-1 text-xs cursor-pointer">
+                                  <input
+                                    type="radio"
+                                    name={`desc-${cveId}`}
+                                    checked={descriptionChoices[cveId] === 'keep'}
+                                    onChange={() => setDescriptionChoices(prev => ({ ...prev, [cveId]: 'keep' }))}
+                                    className="text-blue-600"
+                                  />
+                                  Keep existing
+                                </label>
+                                <label className="flex items-center gap-1 text-xs cursor-pointer">
+                                  <input
+                                    type="radio"
+                                    name={`desc-${cveId}`}
+                                    checked={descriptionChoices[cveId] === 'nvd'}
+                                    onChange={() => setDescriptionChoices(prev => ({ ...prev, [cveId]: 'nvd' }))}
+                                    className="text-green-600"
+                                  />
+                                  Use NVD
+                                </label>
+                              </div>
+                            </div>
+                          )}
+                        </div>
+                      </div>
+                    </div>
+                  );
+                })}
+              </div>
+            </div>
+          )}
+
+          {/* Applying Phase */}
+          {phase === 'applying' && (
+            <div className="text-center py-12">
+              <Loader className="w-10 h-10 text-green-600 animate-spin mx-auto mb-4" />
+              <p className="text-lg text-gray-700">Applying changes...</p>
+            </div>
+          )}
+
+          {/* Done Phase */}
+          {phase === 'done' && applyResult && (
+            <div className="text-center py-8">
+              {applyResult.error ? (
+                <>
+                  <AlertCircle className="w-12 h-12 text-red-500 mx-auto mb-4" />
+                  <p className="text-lg text-red-700 font-medium mb-2">Sync failed</p>
+                  <p className="text-sm text-gray-600">{applyResult.error}</p>
+                </>
+              ) : (
+                <>
+                  <CheckCircle className="w-12 h-12 text-green-500 mx-auto mb-4" />
+                  <p className="text-lg text-green-700 font-medium mb-2">Sync complete</p>
+                  <p className="text-sm text-gray-600">
+                    {applyResult.updated} row{applyResult.updated !== 1 ? 's' : ''} updated
+                  </p>
+                  {applyResult.errors && applyResult.errors.length > 0 && (
+                    <p className="text-sm text-amber-600 mt-2">
+                      {applyResult.errors.length} error{applyResult.errors.length !== 1 ? 's' : ''} occurred
+                    </p>
+                  )}
+                </>
+              )}
+            </div>
+          )}
+        </div>
+
+        {/* Footer */}
+        <div className="p-6 border-t border-gray-200 flex justify-end gap-3 flex-shrink-0">
+          {phase === 'review' && (
+            <>
+              <button
+                onClick={onClose}
+                className="px-4 py-2 bg-gray-200 text-gray-700 rounded-lg hover:bg-gray-300 transition-colors"
+              >
+                Cancel
+              </button>
+              <button
+                onClick={applyChanges}
+                disabled={getChangesCount() === 0}
+                className="px-6 py-2 bg-green-600 text-white rounded-lg hover:bg-green-700 transition-colors font-medium shadow-md disabled:opacity-50"
+              >
+                Apply {getChangesCount()} Change{getChangesCount() !== 1 ? 's' : ''}
+              </button>
+            </>
+          )}
+          {phase === 'done' && (
+            <button
+              onClick={onClose}
+              className="px-6 py-2 bg-[#0476D9] text-white rounded-lg hover:bg-[#0360B8] transition-colors font-medium shadow-md"
+            >
+              Close
+            </button>
+          )}
+        </div>
+      </div>
+    </div>
+  );
+}