CVE-2026-33806 (GCVE-0-2026-33806)

Vulnerability from cvelistv5 – Published: 2026-04-15 00:14 – Updated: 2026-04-15 16:13
VLAI?
Title
fastify vulnerable to Body Schema Validation Bypass via Leading Space in Content-Type Header
Summary
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.
CWE
  • CWE-1287 - Improper Validation of Specified Type of Input
Assigner
Impacted products
Vendor Product Version
fastify fastify Affected: 5.3.2 , < 5.8.5 (semver)
Unaffected: 5.8.5 (semver)
Create a notification for this product.
Credits
mcollina climba03003 jsumners UlisesGascon Vyntral
Show details on NVD website

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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