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TI-2026-06842 Aliases CVE-2026-7768GHSA-qxhc-wx3p-2wmg

@fastify/accepts-serializer vulnerable to Denial of Service via Unbounded Accept Header Cache Growth

Priority LOW 39CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-770.

Summary

@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, eventually exhausting the Node.js heap and crashing the process. Versions <= 6.0.3 are affected. Update to 6.0.4 or later, which bounds the cache via an LRU with a default size of 100 entries, configurable through the new cacheSize plugin option.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00284 21st percentileScored 2026-11-07
Fix Fixed @fastify/accepts-serializer (@fastify/accepts-serializer): 6.0.4@fastify/accepts-serializer (npm): 6.0.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
@fastify/accepts-serializer@fastify/accepts-serializerbefore 6.0.46.0.4Patch availableCNA
—@fastify/accepts-serializer (npm)before 6.0.46.0.4Patch availableGHSA-qxhc-wx3p-2wmg
  • @fastify/accepts-serializer Vendor@fastify/accepts-serializer Affected before 6.0.4 Fixed in 6.0.4 Patch available CNA
  • @fastify/accepts-serializer (npm) Vendor— Affected before 6.0.4 Fixed in 6.0.4 Patch available GHSA-qxhc-wx3p-2wmg

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fastify:fastify\/accepts-serializer:*:*:*:*:*:node.js:*:*before 6.0.4Vulnerablefastify
  • cpe:2.3:a:fastify:fastify\/accepts-serializer:*:*:*:*:*:node.js:*:* Versions before 6.0.4 Vulnerable ·fastify

Remediation

  • Fix · CNA @fastify/accepts-serializer (@fastify/accepts-serializer) Fixed in 6.0.4
  • Fix · GHSA-qxhc-wx3p-2wmg @fastify/accepts-serializer (npm) Fixed in 6.0.4 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-7768
  2. 2026-10-03 Alias added: GHSA-qxhc-wx3p-2wmg

References

Advisory 3

Other 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences