Resource exhaustion in Fastify Fastify\/accepts-Serializer
CVE-2026-7768
@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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (39.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Fastify Fastify\/accepts-Serializer
- @Fastify/accepts-Serializer — versions 0, 6.0.4
Weakness classification (CWE)
References
- ce714d77-add3-4f53-aff5-83d477b104bb (Vendor Advisory)
- ce714d77-add3-4f53-aff5-83d477b104bb (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-7768?
- CVE-2026-7768 is a high-severity vulnerability in Fastify Fastify\/accepts-Serializer, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-05-04.
- How severe is CVE-2026-7768?
- High severity. CVSS v3 base score is 7.5 out of 10.