Vulnerability Description
Impact: Fastify applications using schema.body.content for per-content-type body validation can have validation bypassed entirely by prepending a space to the Content-Type header. The body is still parsed correctly but schema validation is skipped. This is a regression introduced in fastify >= 5.3.2 by the fix for CVE-2025-32442 Patches: Upgrade to fastify v5.8.5 or later. Workarounds: None. Upgrade to the patched version.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Fastify | Fastify | >= 5.3.2, < 5.8.5 |
Related Weaknesses (CWE)
References
- https://cna.openjsf.org/security-advisories.htmlVendor Advisory
- https://github.com/fastify/fastify/security/advisories/GHSA-mg2h-6x62-wpwcNot Applicable
FAQ
What is CVE-2026-33806?
CVE-2026-33806 is a vulnerability with a CVSS score of 7.5 (HIGH). Impact: Fastify applications using schema.body.content for per-content-type body validation can have validation bypassed entirely by prepending a space to the Content-Type header. The body is still p...
How severe is CVE-2026-33806?
CVE-2026-33806 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-33806?
Check the references section above for vendor advisories and patch information. Affected products include: Fastify Fastify.