CVE-2026-33806: fallo de gravedad alta en fastify
fastify vulnerable to Body Schema Validation Bypass via Leading Space in Content-Type Header
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.5epss 0.4%
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Productos afectados
fastify · fastifyCVEs relacionadas — fastify
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Referencias
https://access.redhat.com/security/cve/CVE-2026-33806https://bugzilla.redhat.com/show_bug.cgi?id=2458596https://cna.openjsf.org/security-advisories.htmlhttps://github.com/fastify/fastify/security/advisories/GHSA-mg2h-6x62-wpwchttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33806.json