feat: add CVE tooltip on hover in Reporting Page

- Add GET /api/cves/:cveId/tooltip backend endpoint with description truncation
- Create CveTooltip portal component with caching, severity badges, and viewport-aware positioning
- Integrate tooltip into ReportingPage with 300ms hover delay on CVE badge spans

.kiro/specs/cve-tooltip-hover/.config.kiro

@@ -0,0 +1 @@
+{"specId": "b8855eb4-3949-426e-86ac-36fe069a6bb1", "workflowType": "requirements-first", "specType": "feature"}

.kiro/specs/cve-tooltip-hover/design.md

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+# Design Document: CVE Tooltip Hover
+
+## Overview
+
+This feature adds a hover tooltip to CVE badges in the Reporting Page findings table. When a user pauses their cursor over a CVE identifier badge, the system fetches a brief description and severity from the backend and displays it in a styled floating tooltip. Responses are cached in-memory to avoid redundant API calls, and a 300ms hover delay prevents tooltip flicker during fast mouse movement.
+
+The implementation spans two layers:
+1. A new lightweight backend endpoint (`/api/cves/:cveId/tooltip`) that queries the existing `cves` SQLite table and returns a trimmed response.
+2. A frontend `CveTooltip` component rendered via a React portal, with an in-memory cache (React ref), hover delay timer, and viewport-aware positioning.
+
+## Architecture
+
+```mermaid
+sequenceDiagram
+    participant User
+    participant CVEBadge as CVE Badge (ReportingPage)
+    participant Tooltip as CveTooltip Component
+    participant Cache as Tooltip Cache (useRef)
+    participant API as /api/cves/:cveId/tooltip
+    participant DB as SQLite (cves table)
+
+    User->>CVEBadge: mouseenter
+    CVEBadge->>Tooltip: start 300ms delay timer
+    Note over Tooltip: If mouseout before 300ms, cancel
+
+    alt Cache hit
+        Tooltip->>Cache: lookup(cveId)
+        Cache-->>Tooltip: cached data
+        Tooltip->>User: show tooltip (or skip if exists:false)
+    else Cache miss
+        Tooltip->>API: GET /api/cves/:cveId/tooltip
+        API->>DB: SELECT cve_id, description, severity FROM cves WHERE cve_id = ?
+        DB-->>API: row or null
+        API-->>Tooltip: { exists, cve_id, description, severity }
+        Tooltip->>Cache: store response
+        Tooltip->>User: show tooltip (or skip if exists:false)
+    end
+
+    User->>CVEBadge: mouseleave
+    CVEBadge->>Tooltip: hide + clear timer
+```
+
+### Key Design Decisions
+
+1. **Inline endpoint in server.js** — The tooltip endpoint is a single GET route on the existing `/api/cves` path prefix. It follows the pattern of other simple CVE endpoints already defined inline in `server.js` (e.g., `/api/cves/check/:cveId`, `/api/cves/:cveId/vendors`). No separate route module needed.
+
+2. **React portal for tooltip rendering** — The tooltip is rendered via `ReactDOM.createPortal` to `document.body`, avoiding overflow/clipping issues from the table's scroll container. The ReportingPage already imports `ReactDOM` for other portal usage.
+
+3. **useRef for cache instead of useState** — The cache is a plain `Map` stored in a `useRef`. This avoids re-renders when cache entries are added and persists across renders without triggering updates. The cache is cleared when the findings data is re-synced.
+
+4. **Single shared tooltip instance** — Only one tooltip is visible at a time. The parent component tracks which CVE badge is hovered and passes the active CVE ID + badge position to the tooltip component.
+
+## Components and Interfaces
+
+### Backend
+
+#### `GET /api/cves/:cveId/tooltip`
+
+Added inline in `server.js` alongside existing CVE endpoints.
+
+- **Auth**: `requireAuth(db)` — session cookie required
+- **Params**: `:cveId` — validated against `CVE_ID_PATTERN` (`/^CVE-\d{4}-\d{4,}$/`)
+- **Query**: `SELECT cve_id, description, severity FROM cves WHERE cve_id = ? LIMIT 1`
+- **Response (found)**:
+  ```json
+  {
+    "exists": true,
+    "cve_id": "CVE-2024-12345",
+    "description": "A vulnerability in...",
+    "severity": "High"
+  }
+  ```
+- **Response (not found)**:
+  ```json
+  { "exists": false }
+  ```
+- **Description truncation**: If `description.length > 300`, return `description.substring(0, 300) + '…'`
+
+### Frontend
+
+#### `CveTooltip` Component (new file: `frontend/src/components/CveTooltip.js`)
+
+A portal-rendered tooltip that receives positioning data and CVE info.
+
+**Props:**
+| Prop | Type | Description |
+|------|------|-------------|
+| `cveId` | `string \| null` | The CVE ID to display. `null` hides the tooltip. |
+| `anchorRect` | `DOMRect \| null` | Bounding rect of the hovered badge for positioning. |
+| `cache` | `React.MutableRefObject<Map>` | Shared cache ref from parent. |
+
+**Internal state:**
+- `data` — fetched tooltip payload (`{ exists, cve_id, description, severity }` or `null`)
+- `loading` — boolean, true while fetch is in-flight
+
+**Behavior:**
+1. When `cveId` changes to a non-null value, check `cache.current` for the CVE ID.
+2. If cached and `exists: false`, render nothing.
+3. If cached and `exists: true`, display immediately.
+4. If not cached, set `loading = true`, fetch from API, store result in cache, set `loading = false`.
+5. Position the tooltip above the badge by default. If the tooltip would overflow the top of the viewport, position it below instead.
+6. Render via `ReactDOM.createPortal` to `document.body`.
+
+#### ReportingPage Integration
+
+Modifications to the existing `renderCell` function for the `'cves'` case:
+
+- Add `onMouseEnter` / `onMouseLeave` handlers to each CVE badge `<span>`.
+- `onMouseEnter`: Start a 300ms `setTimeout`. On fire, set active CVE ID + badge `getBoundingClientRect()` into state.
+- `onMouseLeave`: Clear the timeout. Set active CVE ID to `null`.
+- Render a single `<CveTooltip>` instance at the bottom of the component, passing the active CVE ID, anchor rect, and cache ref.
+- On data sync (when findings are refreshed), call `cache.current.clear()`.
+
+## Data Models
+
+### Existing: `cves` Table (SQLite)
+
+The tooltip endpoint queries the existing table. No schema changes required.
+
+```sql
+CREATE TABLE cves (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    cve_id TEXT NOT NULL,
+    vendor TEXT NOT NULL,
+    severity TEXT CHECK(severity IN ('Critical', 'High', 'Medium', 'Low')),
+    description TEXT,
+    published_date TEXT,
+    status TEXT DEFAULT 'Open',
+    created_by INTEGER,
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    UNIQUE(cve_id, vendor)
+);
+```
+
+The query uses `LIMIT 1` since a CVE may have multiple vendor rows — the description and severity from any row suffice for the tooltip blurb.
+
+### Frontend Cache Structure
+
+```javascript
+// cache.current is a Map<string, object>
+// Key: CVE ID string (e.g. "CVE-2024-12345")
+// Value: API response object
+//   { exists: false }
+//   OR
+//   { exists: true, cve_id: string, description: string, severity: string }
+```
+
+
+## Correctness Properties
+
+*A property is a characteristic or behavior that should hold true across all valid executions of a system — essentially, a formal statement about what the system should do. Properties serve as the bridge between human-readable specifications and machine-verifiable correctness guarantees.*
+
+### Property 1: Tooltip endpoint returns correct data for existing CVEs
+
+*For any* CVE record inserted into the `cves` table with a valid `cve_id`, `description`, and `severity`, a GET request to `/api/cves/:cveId/tooltip` SHALL return `{ exists: true }` with the matching `cve_id` and `severity`, and a `description` that is either the original (if ≤ 300 chars) or truncated to 300 chars + ellipsis.
+
+**Validates: Requirements 1.1, 1.3, 1.5**
+
+### Property 2: Description truncation preserves content and enforces length
+
+*For any* string of arbitrary length, the truncation function SHALL return the original string unchanged if its length is ≤ 300, or return exactly the first 300 characters followed by "…" if its length exceeds 300. In both cases, the output starts with the same characters as the input.
+
+**Validates: Requirements 1.5**
+
+### Property 3: Tooltip positioning flips based on available viewport space
+
+*For any* anchor rectangle position and viewport height, the tooltip SHALL be positioned above the anchor when `anchorRect.top` provides sufficient space for the tooltip height, and below the anchor otherwise. The tooltip SHALL never overflow the top or bottom of the viewport.
+
+**Validates: Requirements 3.1, 3.2**
+
+### Property 4: Cache round-trip — fetch then cache-hit avoids network call
+
+*For any* CVE ID, after the tooltip system fetches data from the API and stores it in the cache, a subsequent tooltip request for the same CVE ID SHALL return the identical cached data object without making an additional network request.
+
+**Validates: Requirements 4.1, 4.2**
+
+## Error Handling
+
+| Scenario | Layer | Behavior |
+|----------|-------|----------|
+| Invalid CVE ID format in URL param | Backend | Return `400 { error: 'Invalid CVE ID format.' }` |
+| Database query error | Backend | Log error, return `500 { error: 'Internal server error.' }` |
+| No session cookie / expired session | Backend | `requireAuth` middleware returns `401` |
+| Network error during fetch | Frontend | Catch error, hide tooltip (do not cache failures), log to console |
+| Fetch timeout / slow response | Frontend | Show loading state; if user moves away, cancel via AbortController |
+| Component unmounts during fetch | Frontend | AbortController signal aborts in-flight request, no state update |
+
+**Key principle**: Transient errors (network failures, timeouts) are NOT cached. Only successful API responses (both `exists: true` and `exists: false`) are stored in the cache. This ensures a retry on next hover for failed requests.
+
+## Testing Strategy
+
+### Unit Tests (Example-Based)
+
+| Test | Validates |
+|------|-----------|
+| Endpoint returns `{ exists: false }` for unknown CVE ID | Req 1.2 |
+| Endpoint returns 401 without session cookie | Req 1.4 |
+| Endpoint returns 400 for malformed CVE ID (e.g. "not-a-cve") | Req 1.1 (error path) |
+| Tooltip appears after 300ms hover delay | Req 5.1 |
+| Tooltip cancelled if mouseout before 300ms | Req 5.2 |
+| Tooltip hidden on mouseleave | Req 2.2 |
+| Loading indicator shown while fetching | Req 2.5 |
+| No tooltip shown when API returns `exists: false` | Req 2.6 |
+| Severity badge uses correct color per level | Req 2.4 |
+| Tooltip has max-width of 320px | Req 3.3 |
+| Tooltip includes directional arrow element | Req 3.5 |
+| Cache cleared on data sync/refresh | Req 4.4 |
+| Cached `exists: false` suppresses tooltip and API call | Req 4.3 |
+
+### Property-Based Tests
+
+Property-based tests use **fast-check** (JavaScript PBT library, already compatible with the Jest/react-scripts test runner).
+
+Each property test runs a minimum of **100 iterations**.
+
+| Property | Tag | Focus |
+|----------|-----|-------|
+| Property 1 | `Feature: cve-tooltip-hover, Property 1: Tooltip endpoint returns correct data for existing CVEs` | Generate random CVE records (varying description lengths 0–1000, all 4 severity levels), insert into test DB, call endpoint, verify response shape and truncation |
+| Property 2 | `Feature: cve-tooltip-hover, Property 2: Description truncation preserves content and enforces length` | Generate random strings of length 0–2000, apply truncation function, verify length invariant and prefix preservation |
+| Property 3 | `Feature: cve-tooltip-hover, Property 3: Tooltip positioning flips based on available viewport space` | Generate random anchorRect.top (0–2000), tooltip height (50–200), viewport height (400–1200), verify position is within viewport bounds |
+| Property 4 | `Feature: cve-tooltip-hover, Property 4: Cache round-trip` | Generate random CVE IDs and response payloads, store in cache Map, verify subsequent lookups return identical objects and no fetch is triggered |
+
+### Test Configuration
+
+- Test runner: `react-scripts test` (Jest) — already configured in the project
+- PBT library: `fast-check` — install via `npm install --save-dev fast-check` in the `frontend/` directory
+- Backend endpoint tests: Use supertest or direct handler invocation with a test SQLite DB
+- Frontend component tests: React Testing Library with mocked fetch

.kiro/specs/cve-tooltip-hover/requirements.md

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+# Requirements Document
+
+## Introduction
+
+Add a hover tooltip to CVE badges in the Reporting Page (vuln triage view). When a user hovers over a CVE identifier badge in the findings table, the system checks whether that CVE exists in the local SQLite database. If it does, a small tooltip appears showing a brief description/blurb about that CVE. CVEs not present in the database show no tooltip.
+
+## Glossary
+
+- **Reporting_Page**: The vulnerability triage view at `frontend/src/components/pages/ReportingPage.js` that displays Ivanti host findings in a sortable, filterable table.
+- **CVE_Badge**: The styled `<span>` element in the CVEs column of the findings table that displays a CVE identifier (e.g. CVE-2024-12345) with a purple pill/box appearance.
+- **CVE_Tooltip**: A small floating box that appears on mouse hover over a CVE_Badge, displaying a text blurb about the CVE.
+- **CVE_Database**: The `cves` table in the SQLite database (`backend/cve_database.db`) that stores CVE records including descriptions, severity, and vendor information.
+- **Tooltip_Cache**: An in-memory lookup (React state or ref) that stores previously fetched CVE descriptions to avoid redundant API calls during the same session.
+- **API_Server**: The Express backend at `backend/server.js` that serves CVE data via `/api` endpoints.
+
+## Requirements
+
+### Requirement 1: CVE Tooltip Data Endpoint
+
+**User Story:** As a frontend component, I want to fetch a brief description for a given CVE ID, so that the tooltip can display relevant information without loading unnecessary data.
+
+#### Acceptance Criteria
+
+1. WHEN a GET request is made to `/api/cves/:cveId/tooltip`, THE API_Server SHALL return a JSON object containing the `cve_id`, `description`, and `severity` fields for the matching CVE record.
+2. WHEN a GET request is made to `/api/cves/:cveId/tooltip` for a CVE ID that does not exist in the CVE_Database, THE API_Server SHALL return a JSON object with `{ exists: false }` and HTTP status 200.
+3. WHEN a GET request is made to `/api/cves/:cveId/tooltip` for a CVE ID that exists in the CVE_Database, THE API_Server SHALL return a JSON object with `{ exists: true, cve_id, description, severity }` and HTTP status 200.
+4. THE API_Server SHALL require a valid session cookie for the `/api/cves/:cveId/tooltip` endpoint.
+5. WHEN the `description` field exceeds 300 characters, THE API_Server SHALL truncate the description to 300 characters and append an ellipsis ("…").
+
+### Requirement 2: Tooltip Display on CVE Badge Hover
+
+**User Story:** As a security analyst triaging findings, I want to see a brief description of a CVE when I hover over its badge in the findings table, so that I can quickly understand the vulnerability without leaving the page.
+
+#### Acceptance Criteria
+
+1. WHEN the user hovers the mouse cursor over a CVE_Badge in the Reporting_Page findings table, THE Reporting_Page SHALL display a CVE_Tooltip near the hovered badge.
+2. WHEN the user moves the mouse cursor away from the CVE_Badge, THE Reporting_Page SHALL hide the CVE_Tooltip.
+3. THE CVE_Tooltip SHALL display the CVE description text returned by the API_Server.
+4. THE CVE_Tooltip SHALL display the severity level of the CVE using the existing severity color scheme (Critical: red, High: amber, Medium: sky blue, Low: emerald).
+5. WHILE the CVE data is being fetched from the API_Server, THE CVE_Tooltip SHALL display a loading indicator.
+6. WHEN the API_Server returns `exists: false` for a CVE ID, THE Reporting_Page SHALL not display a CVE_Tooltip for that badge.
+
+### Requirement 3: Tooltip Positioning and Styling
+
+**User Story:** As a security analyst, I want the CVE tooltip to be readable and not obstruct other table content, so that I can continue triaging while viewing CVE details.
+
+#### Acceptance Criteria
+
+1. THE CVE_Tooltip SHALL appear above the hovered CVE_Badge by default.
+2. WHEN there is insufficient viewport space above the CVE_Badge, THE CVE_Tooltip SHALL appear below the badge instead.
+3. THE CVE_Tooltip SHALL have a maximum width of 320 pixels.
+4. THE CVE_Tooltip SHALL use the design system dark theme styling: dark background gradient, accent border, monospace font for the CVE ID, and standard font for the description text.
+5. THE CVE_Tooltip SHALL include a small directional arrow pointing toward the CVE_Badge.
+
+### Requirement 4: Tooltip Response Caching
+
+**User Story:** As a security analyst scrolling through many findings, I want CVE tooltip data to load instantly for CVEs I have already hovered over, so that repeated hovers do not cause redundant network requests.
+
+#### Acceptance Criteria
+
+1. WHEN the Reporting_Page fetches tooltip data for a CVE ID, THE Tooltip_Cache SHALL store the response for that CVE ID.
+2. WHEN the user hovers over a CVE_Badge for a CVE ID that exists in the Tooltip_Cache, THE Reporting_Page SHALL display the cached data without making an API call.
+3. WHEN the user hovers over a CVE_Badge for a CVE ID where the Tooltip_Cache stores `exists: false`, THE Reporting_Page SHALL not display a tooltip and SHALL not make an API call.
+4. WHEN the Reporting_Page performs a full data sync (refresh), THE Tooltip_Cache SHALL be cleared.
+
+### Requirement 5: Hover Delay
+
+**User Story:** As a security analyst, I want the tooltip to only appear after a brief pause on a CVE badge, so that tooltips do not flash distractingly when I move the mouse across the table quickly.
+
+#### Acceptance Criteria
+
+1. WHEN the user hovers over a CVE_Badge, THE Reporting_Page SHALL wait 300 milliseconds before initiating the tooltip display sequence.
+2. IF the user moves the mouse away from the CVE_Badge before 300 milliseconds have elapsed, THEN THE Reporting_Page SHALL cancel the tooltip display and not make an API call.

.kiro/specs/cve-tooltip-hover/tasks.md

@@ -0,0 +1,107 @@
+# Implementation Plan: CVE Tooltip Hover
+
+## Overview
+
+Implement a hover tooltip for CVE badges in the Reporting Page findings table. The feature spans a backend endpoint (`GET /api/cves/:cveId/tooltip`) and a frontend `CveTooltip` portal component with in-memory caching and 300ms hover delay. Tasks are ordered backend-first, then frontend component, then integration, with property tests alongside each layer.
+
+## Tasks
+
+- [x] 1. Add backend tooltip endpoint
+  - [x] 1.1 Add `GET /api/cves/:cveId/tooltip` route inline in `backend/server.js`
+    - Place it alongside existing CVE endpoints (after `/api/cves/:cveId/vendors`)
+    - Validate `:cveId` against existing `CVE_ID_PATTERN`; return 400 for invalid format
+    - Query: `SELECT cve_id, description, severity FROM cves WHERE cve_id = ? LIMIT 1`
+    - If no row: return `{ exists: false }` with status 200
+    - If row found: truncate `description` to 300 chars + "…" if needed, return `{ exists: true, cve_id, description, severity }`
+    - Protect with `requireAuth(db)` middleware
+    - _Requirements: 1.1, 1.2, 1.3, 1.4, 1.5_
+
+  - [ ]* 1.2 Write property test for tooltip endpoint data correctness
+    - **Property 1: Tooltip endpoint returns correct data for existing CVEs**
+    - Install `fast-check` as dev dependency in `frontend/` (shared test runner)
+    - Generate random CVE records with description lengths 0–1000 and all 4 severity levels
+    - Verify response shape, truncation at 300 chars, and prefix preservation
+    - **Validates: Requirements 1.1, 1.3, 1.5**
+
+  - [ ]* 1.3 Write property test for description truncation
+    - **Property 2: Description truncation preserves content and enforces length**
+    - Extract truncation logic into a testable pure function
+    - Generate random strings of length 0–2000, verify length invariant and prefix match
+    - **Validates: Requirements 1.5**
+
+- [x] 2. Checkpoint — Verify backend endpoint
+  - Ensure all tests pass, ask the user if questions arise.
+
+- [x] 3. Create CveTooltip frontend component
+  - [x] 3.1 Create `frontend/src/components/CveTooltip.js`
+    - Portal-rendered component using `ReactDOM.createPortal` to `document.body`
+    - Props: `cveId` (string|null), `anchorRect` (DOMRect|null), `cache` (useRef Map)
+    - Internal state: `data`, `loading`
+    - On `cveId` change: check cache → if miss, fetch from `/api/cves/:cveId/tooltip` with AbortController
+    - If cached `exists: false` or fetch returns `exists: false`, render nothing
+    - Show loading spinner (Loader from lucide-react) while fetching
+    - Display: CVE ID in monospace, severity badge with design system colors, description text
+    - Max-width 320px, dark theme gradient background, accent border, directional arrow
+    - Position above anchor by default; flip below if insufficient viewport space above
+    - Do not cache transient errors (network failures)
+    - _Requirements: 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 3.1, 3.2, 3.3, 3.4, 3.5_
+
+  - [ ]* 3.2 Write property test for tooltip positioning logic
+    - **Property 3: Tooltip positioning flips based on available viewport space**
+    - Extract positioning calculation into a pure function
+    - Generate random anchorRect.top (0–2000), tooltip height (50–200), viewport height (400–1200)
+    - Verify tooltip never overflows top or bottom of viewport
+    - **Validates: Requirements 3.1, 3.2**
+
+  - [ ]* 3.3 Write unit tests for CveTooltip component
+    - Test loading state renders spinner
+    - Test `exists: false` renders nothing
+    - Test severity badge uses correct color per level
+    - Test max-width constraint
+    - Test directional arrow element is present
+    - _Requirements: 2.4, 2.5, 2.6, 3.3, 3.5_
+
+- [x] 4. Checkpoint — Verify CveTooltip component
+  - Ensure all tests pass, ask the user if questions arise.
+
+- [x] 5. Integrate tooltip into ReportingPage
+  - [x] 5.1 Add hover state and cache ref to ReportingPage
+    - Add state: `tooltipCveId` (string|null), `tooltipAnchorRect` (DOMRect|null)
+    - Add `useRef(new Map())` for tooltip cache
+    - Add `useRef` for hover delay timer
+    - Clear cache when findings data is re-synced (inside existing sync callback)
+    - _Requirements: 4.1, 4.4, 5.1_
+
+  - [x] 5.2 Add mouseenter/mouseleave handlers to CVE badge spans
+    - In the `renderCell` function for the `'cves'` column case, wrap each CVE badge `<span>` with `onMouseEnter` and `onMouseLeave`
+    - `onMouseEnter`: start 300ms setTimeout; on fire, set `tooltipCveId` and `tooltipAnchorRect` from `getBoundingClientRect()`
+    - `onMouseLeave`: clear timeout, set `tooltipCveId` to null
+    - _Requirements: 2.1, 2.2, 5.1, 5.2_
+
+  - [x] 5.3 Render CveTooltip instance in ReportingPage
+    - Add single `<CveTooltip>` at the bottom of the ReportingPage return, passing `tooltipCveId`, `tooltipAnchorRect`, and cache ref
+    - _Requirements: 2.1, 4.2, 4.3_
+
+  - [ ]* 5.4 Write property test for cache round-trip behavior
+    - **Property 4: Cache round-trip — fetch then cache-hit avoids network call**
+    - Generate random CVE IDs and response payloads, store in Map, verify lookups return identical objects
+    - **Validates: Requirements 4.1, 4.2**
+
+  - [ ]* 5.5 Write unit tests for hover delay and cache integration
+    - Test tooltip appears after 300ms delay (use fake timers)
+    - Test tooltip cancelled if mouseout before 300ms
+    - Test cached `exists: false` suppresses tooltip and API call
+    - Test cache cleared on data sync/refresh
+    - _Requirements: 4.3, 4.4, 5.1, 5.2_
+
+- [x] 6. Final checkpoint — Ensure all tests pass
+  - Ensure all tests pass, ask the user if questions arise.
+
+## Notes
+
+- Tasks marked with `*` are optional and can be skipped for faster MVP
+- Each task references specific requirements for traceability
+- Checkpoints ensure incremental validation
+- Property tests validate universal correctness properties from the design document
+- Unit tests validate specific examples and edge cases
+- The project uses plain JavaScript (no TypeScript), fast-check for PBT, and react-scripts test (Jest)

backend/server.js

@@ -348,6 +348,29 @@ app.get('/api/cves/:cveId/vendors', requireAuth(db), (req, res) => {
     });
 });
 
+// Get tooltip data for a specific CVE (authenticated users)
+app.get('/api/cves/:cveId/tooltip', requireAuth(db), (req, res) => {
+    const { cveId } = req.params;
+
+    if (!CVE_ID_PATTERN.test(cveId)) {
+        return res.status(400).json({ error: 'Invalid CVE ID format.' });
+    }
+
+    db.get('SELECT cve_id, description, severity FROM cves WHERE cve_id = ? LIMIT 1', [cveId], (err, row) => {
+        if (err) {
+            console.error('Error fetching CVE tooltip:', err);
+            return res.status(500).json({ error: 'Internal server error.' });
+        }
+        if (!row) {
+            return res.json({ exists: false });
+        }
+        let description = row.description || '';
+        if (description.length > 300) {
+            description = description.substring(0, 300) + '\u2026';
+        }
+        res.json({ exists: true, cve_id: row.cve_id, description, severity: row.severity });
+    });
+});
 
 // Compliance export — reads from cve_document_status view
 app.get('/api/cves/compliance', requireAuth(db), (req, res) => {

frontend/src/components/CveTooltip.js

@@ -0,0 +1,243 @@
+import React, { useState, useEffect } from 'react';
+import ReactDOM from 'react-dom';
+import { Loader } from 'lucide-react';
+
+const API_BASE = process.env.REACT_APP_API_BASE || 'http://localhost:3001/api';
+
+// ---------------------------------------------------------------------------
+// Severity color mapping — matches DESIGN_SYSTEM.md badge colors
+// ---------------------------------------------------------------------------
+const SEVERITY_COLORS = {
+  Critical: { border: '#EF4444', bg: 'rgba(239, 68, 68, 0.25)', text: '#FCA5A5', dot: '#EF4444' },
+  High:     { border: '#F59E0B', bg: 'rgba(245, 158, 11, 0.25)', text: '#FCD34D', dot: '#F59E0B' },
+  Medium:   { border: '#0EA5E9', bg: 'rgba(14, 165, 233, 0.25)', text: '#7DD3FC', dot: '#0EA5E9' },
+  Low:      { border: '#10B981', bg: 'rgba(16, 185, 129, 0.25)', text: '#6EE7B7', dot: '#10B981' },
+};
+
+// ---------------------------------------------------------------------------
+// Pure positioning function — exported for testability
+// ---------------------------------------------------------------------------
+const TOOLTIP_GAP = 8;
+const ARROW_SIZE = 6;
+
+export function calcTooltipPosition(anchorRect, tooltipHeight, viewportHeight) {
+  const spaceAbove = anchorRect.top;
+  const spaceBelow = viewportHeight - anchorRect.bottom;
+  const needed = tooltipHeight + TOOLTIP_GAP + ARROW_SIZE;
+
+  const placeAbove = spaceAbove >= needed || spaceAbove >= spaceBelow;
+
+  let top;
+  if (placeAbove) {
+    top = anchorRect.top - tooltipHeight - TOOLTIP_GAP - ARROW_SIZE;
+    if (top < 0) top = 0;
+  } else {
+    top = anchorRect.bottom + TOOLTIP_GAP + ARROW_SIZE;
+    if (top + tooltipHeight > viewportHeight) top = viewportHeight - tooltipHeight;
+  }
+
+  const left = anchorRect.left + anchorRect.width / 2;
+
+  return { top, left, placeAbove };
+}
+
+// ---------------------------------------------------------------------------
+// CveTooltip component
+// ---------------------------------------------------------------------------
+export default function CveTooltip({ cveId, anchorRect, cache }) {
+  const [data, setData] = useState(null);
+  const [loading, setLoading] = useState(false);
+
+  useEffect(() => {
+    if (!cveId) {
+      setData(null);
+      setLoading(false);
+      return;
+    }
+
+    // Check cache first
+    if (cache.current.has(cveId)) {
+      setData(cache.current.get(cveId));
+      setLoading(false);
+      return;
+    }
+
+    // Cache miss — fetch from API
+    const controller = new AbortController();
+    setLoading(true);
+    setData(null);
+
+    fetch(`${API_BASE}/cves/${encodeURIComponent(cveId)}/tooltip`, {
+      credentials: 'include',
+      signal: controller.signal,
+    })
+      .then((res) => {
+        if (!res.ok) throw new Error(`HTTP ${res.status}`);
+        return res.json();
+      })
+      .then((payload) => {
+        cache.current.set(cveId, payload);
+        setData(payload);
+        setLoading(false);
+      })
+      .catch((err) => {
+        if (err.name === 'AbortError') return;
+        // Do not cache transient errors
+        console.error('CveTooltip fetch error:', err);
+        setData(null);
+        setLoading(false);
+      });
+
+    return () => controller.abort();
+  }, [cveId, cache]);
+
+  // Nothing to show
+  if (!cveId || !anchorRect) return null;
+  if (!loading && !data) return null;
+  if (data && data.exists === false) return null;
+
+  const severity = data?.severity || '';
+  const colors = SEVERITY_COLORS[severity] || SEVERITY_COLORS.Medium;
+
+  return ReactDOM.createPortal(
+    <TooltipBody
+      data={data}
+      loading={loading}
+      anchorRect={anchorRect}
+      colors={colors}
+      severity={severity}
+    />,
+    document.body,
+  );
+}
+
+
+// ---------------------------------------------------------------------------
+// TooltipBody — inner component that measures itself for positioning
+// ---------------------------------------------------------------------------
+function TooltipBody({ data, loading, anchorRect, colors, severity }) {
+  const tooltipRef = React.useRef(null);
+  const [pos, setPos] = React.useState({ top: 0, left: 0, placeAbove: true });
+
+  React.useLayoutEffect(() => {
+    if (!tooltipRef.current || !anchorRect) return;
+    const rect = tooltipRef.current.getBoundingClientRect();
+    const vp = window.innerHeight;
+    setPos(calcTooltipPosition(anchorRect, rect.height, vp));
+  }, [anchorRect, data, loading]);
+
+  const tooltipStyle = {
+    position: 'fixed',
+    zIndex: 99999,
+    top: pos.top,
+    left: pos.left,
+    transform: 'translateX(-50%)',
+    maxWidth: 320,
+    minWidth: 200,
+    background: 'linear-gradient(135deg, rgba(30, 41, 59, 0.98), rgba(51, 65, 85, 0.95))',
+    border: `1.5px solid ${colors.border}`,
+    borderRadius: '0.5rem',
+    padding: '0.75rem',
+    boxShadow: `0 8px 24px rgba(0, 0, 0, 0.6), 0 0 16px ${colors.border}33`,
+    pointerEvents: 'none',
+    transition: 'opacity 0.15s ease',
+  };
+
+  // Directional arrow
+  const arrowStyle = {
+    position: 'absolute',
+    left: '50%',
+    transform: 'translateX(-50%)',
+    width: 0,
+    height: 0,
+    borderLeft: `${ARROW_SIZE}px solid transparent`,
+    borderRight: `${ARROW_SIZE}px solid transparent`,
+    ...(pos.placeAbove
+      ? {
+          bottom: -ARROW_SIZE,
+          borderTop: `${ARROW_SIZE}px solid ${colors.border}`,
+          borderBottom: 'none',
+        }
+      : {
+          top: -ARROW_SIZE,
+          borderBottom: `${ARROW_SIZE}px solid ${colors.border}`,
+          borderTop: 'none',
+        }),
+  };
+
+  return (
+    <div ref={tooltipRef} style={tooltipStyle} data-testid="cve-tooltip">
+      {/* Arrow */}
+      <div style={arrowStyle} data-testid="cve-tooltip-arrow" />
+
+      {loading ? (
+        <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'center', padding: '0.5rem 0' }}>
+          <Loader
+            style={{ width: 18, height: 18, color: '#0EA5E9', animation: 'spin 1s linear infinite' }}
+            data-testid="cve-tooltip-loader"
+          />
+        </div>
+      ) : data && data.exists ? (
+        <>
+          {/* CVE ID header */}
+          <div style={{
+            fontFamily: "'JetBrains Mono', monospace",
+            fontSize: '0.8rem',
+            fontWeight: 700,
+            color: '#E2E8F0',
+            marginBottom: '0.4rem',
+            letterSpacing: '0.02em',
+          }}>
+            {data.cve_id}
+          </div>
+
+          {/* Severity badge */}
+          {severity && (
+            <div style={{
+              display: 'inline-flex',
+              alignItems: 'center',
+              gap: '0.35rem',
+              padding: '0.2rem 0.5rem',
+              borderRadius: '0.25rem',
+              border: `1.5px solid ${colors.border}`,
+              background: colors.bg,
+              marginBottom: '0.5rem',
+            }}>
+              {/* Glow dot */}
+              <span style={{
+                width: 7,
+                height: 7,
+                borderRadius: '50%',
+                background: colors.dot,
+                boxShadow: `0 0 6px ${colors.dot}`,
+                flexShrink: 0,
+              }} />
+              <span style={{
+                fontFamily: "'JetBrains Mono', monospace",
+                fontSize: '0.65rem',
+                fontWeight: 700,
+                textTransform: 'uppercase',
+                letterSpacing: '0.04em',
+                color: colors.text,
+              }}>
+                {severity}
+              </span>
+            </div>
+          )}
+
+          {/* Description */}
+          {data.description && (
+            <div style={{
+              fontSize: '0.75rem',
+              lineHeight: 1.5,
+              color: '#CBD5E1',
+              wordBreak: 'break-word',
+            }}>
+              {data.description}
+            </div>
+          )}
+        </>
+      ) : null}
+    </div>
+  );
+}

frontend/src/components/pages/ReportingPage.js

@@ -4,6 +4,7 @@ import { RefreshCw, Loader, AlertCircle, PieChart, ChevronUp, ChevronDown, Chevr
 import * as XLSX from 'xlsx';
 import { useAuth } from '../../contexts/AuthContext';
 import IvantiCountsChart from './IvantiCountsChart';
+import CveTooltip from '../CveTooltip';
 
 const API_BASE = process.env.REACT_APP_API_BASE || 'http://localhost:3001/api';
 const STORAGE_KEY = 'steam_findings_columns_v2';
@@ -920,7 +921,7 @@ function FilterDropdown({ anchorEl, colKey, findings, activeFilter, onFilterChan
 // ---------------------------------------------------------------------------
 // Render a single table cell by column key
 // ---------------------------------------------------------------------------
-function TableCell({ colKey, finding, canWrite }) {
+function TableCell({ colKey, finding, canWrite, onCveMouseEnter, onCveMouseLeave }) {
     switch (colKey) {
         case 'findingId':
             return (
@@ -956,7 +957,12 @@ function TableCell({ colKey, finding, canWrite }) {
                 <td style={{ padding: '0.45rem 0.75rem', minWidth: '160px', maxWidth: '240px' }}>
                     <div style={{ display: 'flex', flexWrap: 'wrap', gap: '0.2rem' }}>
                         {shown.map((cve) => (
-                            <span key={cve} style={{ padding: '0.1rem 0.35rem', borderRadius: '0.2rem', background: 'rgba(139,92,246,0.1)', border: '1px solid rgba(139,92,246,0.3)', color: '#A78BFA', fontFamily: 'monospace', fontSize: '0.65rem', fontWeight: '600', whiteSpace: 'nowrap' }}>
+                            <span
+                                key={cve}
+                                onMouseEnter={onCveMouseEnter ? (e) => onCveMouseEnter(cve, e) : undefined}
+                                onMouseLeave={onCveMouseLeave || undefined}
+                                style={{ padding: '0.1rem 0.35rem', borderRadius: '0.2rem', background: 'rgba(139,92,246,0.1)', border: '1px solid rgba(139,92,246,0.3)', color: '#A78BFA', fontFamily: 'monospace', fontSize: '0.65rem', fontWeight: '600', whiteSpace: 'nowrap' }}
+                            >
                                 {cve}
                             </span>
                         ))}
@@ -2312,11 +2318,32 @@ export default function VulnerabilityTriagePage({ filterDate, filterEXC }) {
     const [batchWorkflowType, setBatchWorkflowType] = useState('FP');
     const [batchVendor, setBatchVendor] = useState('');
 
+    // CVE tooltip state & refs
+    const [tooltipCveId, setTooltipCveId]           = useState(null);
+    const [tooltipAnchorRect, setTooltipAnchorRect] = useState(null);
+    const tooltipCacheRef                           = useRef(new Map());
+    const hoverTimerRef                             = useRef(null);
+
     const updateColumns = useCallback((newOrder) => {
         setColumnOrder(newOrder);
         saveColumnOrder(newOrder);
     }, []);
 
+    // CVE tooltip hover handlers
+    const handleCveMouseEnter = useCallback((cveId, e) => {
+        clearTimeout(hoverTimerRef.current);
+        hoverTimerRef.current = setTimeout(() => {
+            setTooltipCveId(cveId);
+            setTooltipAnchorRect(e.target.getBoundingClientRect());
+        }, 300);
+    }, []);
+
+    const handleCveMouseLeave = useCallback(() => {
+        clearTimeout(hoverTimerRef.current);
+        setTooltipCveId(null);
+        setTooltipAnchorRect(null);
+    }, []);
+
     const applyState = (data) => {
         setTotal(data.total ?? 0);
         setFindings(data.findings || []);
@@ -2358,7 +2385,10 @@ export default function VulnerabilityTriagePage({ filterDate, filterEXC }) {
         try {
             const res  = await fetch(`${API_BASE}/ivanti/findings`, { credentials: 'include' });
             const data = await res.json();
-            if (res.ok) applyState(data);
+            if (res.ok) {
+                applyState(data);
+                tooltipCacheRef.current.clear();
+            }
         } catch (e) {
             console.error('Error loading findings:', e);
         } finally {
@@ -2373,6 +2403,7 @@ export default function VulnerabilityTriagePage({ filterDate, filterEXC }) {
             const data = await res.json();
             if (res.ok) {
                 applyState(data);
+                tooltipCacheRef.current.clear();
                 fetchCounts();           // refresh counts after sync
                 fetchFPWorkflowCounts(); // refresh FP workflow counts after sync
             }
@@ -3182,7 +3213,7 @@ export default function VulnerabilityTriagePage({ filterDate, filterEXC }) {
                                                 />
                                             </td>
                                             {visibleCols.map((col) => (
-                                                <TableCell key={col.key} colKey={col.key} finding={finding} canWrite={canWrite()} />
+                                                <TableCell key={col.key} colKey={col.key} finding={finding} canWrite={canWrite()} onCveMouseEnter={handleCveMouseEnter} onCveMouseLeave={handleCveMouseLeave} />
                                             ))}
                                         </tr>
                                     );
@@ -3245,6 +3276,11 @@ export default function VulnerabilityTriagePage({ filterDate, filterEXC }) {
                 selectedItems={fpModalItems}
                 onSuccess={handleFpWorkflowSuccess}
             />
+            <CveTooltip
+                cveId={tooltipCveId}
+                anchorRect={tooltipAnchorRect}
+                cache={tooltipCacheRef}
+            />
         </div>
     );
 }