PatchTheCVECVE-2026-7768: @fastify/accepts-serializer cached serializer-selection results keyed by the request Accept header without a s
CVE-2026-7768 is a high-severity flaw (CVSS 7.5) affecting fastify\/accepts-serializer. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
@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
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.3% (top 79%) |
| CISA exploited list | No |
| Weakness | CWE-770 |
| Published | 2026-05-04 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-7768?
fastify\/accepts-serializer: upgrade to 6.0.4. Exact commands for each OS are on this page.
Is CVE-2026-7768 being exploited?
CVE-2026-7768 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-7768 affect?
CVE-2026-7768 affects fastify\/accepts-serializer. Severity is high (CVSS 7.5). @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
How urgent is CVE-2026-7768?
Priority 36/100. High severity; Remotely exploitable, no login, no user action