fastify/fastify-accepts-serializer · Security
@fastify/accepts-serializer Vulnerable to Denial of Service via Unbounded Accept Header Cache Growth
- GHSA ID
- GHSA-qxhc-wx3p-2wmg
- CVE ID
- CVE-2026-7768
- Severity
- high
- Published
- Updated
- CVSS
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS v3
- 7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
Impact
@fastify/accepts-serializer cached serializer-selection results keyed by the request Accept header without a size limit or eviction policy. A remote unauthenticated client could send many distinct but matching Accept header variants to make the cache grow unbounded. Under sustained load, this can exhaust the Node.js heap and crash the process.
Patches
Update to @fastify/accepts-serializer >= 6.0.4. The cache is now bounded by an LRU with a default size of 100 entries, configurable via the new cacheSize plugin option.
Workarounds
None. Upgrade is required.
CWEs
- CWE-770 · Allocation of Resources Without Limits or Throttling