Incorrect Regular Expression Affecting fastify package, versions >=5.7.2 <5.8.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published6 Mar 2026
- disclosed5 Mar 2026
- creditSaad Fellahi
Introduced: 5 Mar 2026
NewCVE-2026-3419 (opens in a new tab)How to fix?
Upgrade fastify to version 5.8.1 or higher.
Overview
fastify is an overhead web framework, for Node.js.
Affected versions of this package are vulnerable to Incorrect Regular Expression in the Content-Type header validation. An attacker can cause the server to incorrectly process requests with malformed Content-Type headers by sending values that include trailing invalid characters, allowing these requests to bypass intended validation and be handled by inappropriate content-type parsers.
Workaround
This vulnerability can be mitigated by deploying a WAF rule to protect against this.