CVE-2026-3419 describes a vulnerability in Fastify where it improperly accepts malformed Content-Type headers containing trailing characters, violating RFC 9110. This allows attackers to bypass validation checks and potentially route requests to incorrect content-type parsers, leading to unintended processing. The vulnerability has a medium severity CVSS score of 5.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N), indicating it can be exploited remotely with low complexity to impact integrity. There is currently no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 5.7.2, < 5.8.1CPE match | cpe:2.3:a:fastify:fastify:*:*:*:*:*:node.js:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.4 GitHub mentions.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.