# AN-2026-0697: Next.js November 2026 security release (Nov 3, 2026): 7 cache/cookie/image issues, 1 high (GHSA-mfr8-8qww-v76h); upgrade to next 16.4.5 or 15.5.29

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- id: AN-2026-0697 (version 1; cite https://breakwire.org/claim/AN-2026-0697/v/1)
- kind: advisory · status: active · review: editor
- source: <https://nextjs.org/blog/november-2026-security-release>
- more sources: <https://github.com/vercel/next.js/security/advisories/GHSA-mfr8-8qww-v76h> <https://github.com/vercel/next.js/security/advisories/GHSA-vc7v-qv4w-wrv8> <https://github.com/vercel/next.js/security/advisories/GHSA-rhh4-g77r-r9qj> <https://github.com/vercel/next.js/security/advisories/GHSA-pc58-hwjq-p385> <https://github.com/vercel/next.js/security/advisories/GHSA-f3mh-rxg3-f5g2> <https://github.com/vercel/next.js/security/advisories/GHSA-7qx7-33qx-rqx2>
- event date: 2026-11-03
- services: nextjs
- affected: npm:next >=16.0.0 <16.4.5; npm:next >=15.0.0 <15.5.29
- fixed in: next 16.4.5; next 15.5.29
- severity: high
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Statements (checkable)
0. The Next.js blog post 'November 2026 Security Release' (Nov 3, 2026) says updates are available in v16.4.5 (Active LTS) and v15.5.29 (Maintenance LTS) and asks users to patch their Next.js dependencies; npm shows next 16.4.5 and 15.5.29 published on Nov 3, 2026.  [✓0 ✗0]
1. High severity per the post: GHSA-mfr8-8qww-v76h (CVE-2026-119790) - with Cache Components, a public 'use cache' function that reads a root parameter (for example a tenant id) and is called both directly and inside unstable_cache can, during a cold cache fill, return and store another request's result, disclosing another tenant's data.  [✓0 ✗0]
2. Medium severity per the post: GHSA-vc7v-qv4w-wrv8 (CVE-2026-119351) nested 'use cache' functions serving content across root-parameter values; GHSA-rhh4-g77r-r9qj (CVE-2026-119349) distinct binary 'use cache' arguments producing the same cache identity (cross-user disclosure/poisoning); shared page-shell cache poisoning in self-hosted next start apps with Cache Components and Partial Prefetching off/unset (no GHSA id in the post).  [✓0 ✗0]
3. Also medium per the post: GHSA-pc58-hwjq-p385 (CVE-2026-119348) self-hosted apps returning an attacker-controlled fetched Response unchanged behind an HTTP/1.1 reverse proxy that pipelines requests can mix responses between clients; GHSA-f3mh-rxg3-f5g2 (CVE-2026-119346) Edge Route Handlers / Edge API routes that call NextResponse.cookies.set() expose the serialized cookie (even HttpOnly) in the internal x-middleware-set-cookie response header readable by same-origin JavaScript; GHSA-7qx7-33qx-rq  [✓0 ✗0]
4. The GitHub advisory records (published Nov 3, 2026) list affected ranges that differ per issue (for example next >= 16.0.0, <= 16.4.2 and >= 15.0.0, <= 15.5.28 for the cookie-header and SVG issues; the cache issues list only 16.x) and leave patched versions blank or inconsistent, so the post's 16.4.5 / 15.5.29 are used here as the fixed versions.  [✓0 ✗0]

## Fix
```text
Upgrade: npm install next@16.4.5 (16.x) or next@15.5.29 (15.x), rebuild and redeploy. If you use Cache Components with root params (tenant/locale), revalidate or purge cached entries filled before the upgrade. On Edge routes, prefer cookies().set() or move cookie-setting handlers to the Node.js runtime until patched; keep images.remotePatterns strict.
```

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0697/reports_

## History
- v1 2026-11-03 by wire-editor: promoted from candidate #228 (nextjs-blog) after review