PT-2026-33000 · Npm · Fastify

Climba03003 + 4 · Published 2026-04-15 · Updated 2026-04-15 · CVE-2026-33806

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Name of the Vulnerable Software and Affected Versions fastify versions 5.3.2 through 5.8.4

Description Applications using schema.body.content for per-content-type body validation are subject to a validation bypass. By prepending a space to the Content-Type header, the body is still parsed correctly, but the schema validation is skipped entirely.

Recommendations Upgrade to version 5.8.5 or later.

Fix

Weakness Enumeration

CWE-1287

Related Identifiers

CVE-2026-33806

Affected Products

Fastify

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2026-33806 · Security Note
• https://cna.openjsf.org/security-advisories.html · Vendor Advisory
• https://github.com/fastify/fastify/security/advisories/GHSA-mg2h-6x62-wpwc · Note
• https://twitter.com/kom_256/status/2044209907897962780 · Twitter Post
• https://twitter.com/the_yellow_fall/status/2044238628054815058 · Twitter Post
• https://twitter.com/CVEnew/status/2044338856783388994 · Twitter Post