Next.js vulnerable to cache poisoning via collisions in React Server Component cache-busting (CVE-2026-44582) | HOL Guard CVE

Low · CVSS 3.7CVE-2026-44582GHSA-VFV6-92FF-J949

Next.js vulnerable to cache poisoning via collisions in React Server Component cache-busting

Answer in brief

CVE-2026-44582 records a Low severity (CVSS 3.7) vulnerability in Next.js vulnerable to cache poisoning via collisions in React Server Component cache-busting. The current sources do not mark it as known exploited. The current feed maps next (npm), next (npm), next (npm), next (npm). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published May 6, 2026Updated May 14, 2026Source checked Aug 26, 2026First seen by HOL Aug 25, 2026Material review May 14, 2026

Upstream Advisory

Key facts

Risk: Low · CVSS 3.7
Exploitation: Not marked as known exploited
Affected software: 4 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 3.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps next (npm), next (npm), next (npm), next (npm). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
nextnpm	>=13.4.6<15.5.16	Not reported
nextnpm	>=16.0.0<16.2.5	Not reported
nextnpm	>=13.4.6,<15.5.16	15.5.16
nextnpm	>=16.0.0,<16.2.5	16.2.5

Recommended response

Check inventory. Check lockfiles and deployed manifests for next, next, next.
Review the reported fix. Update next to 15.5.16; next to 16.2.5 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
May 6, 2026
Evidence: source:ghsa:source_dates:source-dates:record
Source modified
May 14, 2026
Evidence: source:ghsa:source_dates:source-dates:record
First seen by HOL
Aug 25, 2026

Sources and claim methodology

Upstream source description

### Impact React Server Component responses can be vulnerable to cache poisoning in deployments that rely on shared caches with insufficient response partitioning. In affected conditions, collisions in the `_rsc` cache-busting value can allow an attacker to poison cache entries so users receive the wrong response variant for a given URL. ### Fix We strengthened the `_rsc` cache-busting mechanism to make practical collisions significantly harder and to better separate response variants that should not share cache entries. ### Workarounds If you cannot upgrade immediately, ensure intermediary caches correctly honor `Vary` for RSC-related request headers, or disable shared caching for affected RSC responses until you can deploy a patched release.

Quoted source text, attributed separately from HOL analysis.