CVE-2026-25223
Fastify's Content-Type header tab character allows body validation bypass
Description
Fastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.2, a validation bypass vulnerability exists in Fastify where request body validation schemas specified by Content-Type can be completely circumvented. By appending a tab character (\t) followed by arbitrary content to the Content-Type header, attackers can bypass body validation while the server still processes the body as the original content type. This issue has been patched in version 5.7.2.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:HIntegrityHigh
A:NAvailabilityNone
Weaknesses
Affected Products
Exploitability
Official Patch Available
Workaround Available
References
https://github.com/fastify/fastify/security/advisories/GHSA-jx2c-rxcm-jvmq
github.com
https://github.com/fastify/fastify/commit/32d7b6add39ddf082d92579a58bea7018c5ac821
github.com
https://hackerone.com/reports/3464114
hackerone.com
and 11 more references View all →
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