fastify/websocket vulnerable to uncaught exception via crash on malformed packet
Impact
Any application using @fastify/websocket could crash if a specific, malformed packet is sent.
All versions of fastify-websocket are also impacted. That module is deprecated, so it will not be patched.
Patches
This has been patched in v7.1.1 (fastify v4) and v5.0.1 (fastify v3).
Workarounds
No known workaround is available. However, it should be possible to attach the error handler manually. The recommended path is upgrading to the patched versions.
Credits
marcolanaro for finding and patching this vulnerability
For more information
If you have any questions or comments about this advisory:
- Open an issue in @fastify/websocket
- Email us at hello@matteocollina.com
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | @fastify/websocket | >= 5.0.0, < 5.0.1, >= 6.0.0, < 7.1.1 | 5.0.1, 7.1.1 |
| npm package | fastify-websocket | <= 4.3.0 | no fix |
References
- https://github.com/fastify/fastify-websocket/security/advisories/GHSA-4pcg-wr6c-h9cq
- https://nvd.nist.gov/vuln/detail/CVE-2022-39386
- https://github.com/fastify/fastify-websocket/pull/228
- https://github.com/fastify/fastify-websocket/commit/7e8c41a51c101c3d5ce88caee4f71d9c29eb2863
- https://github.com/fastify/fastify-websocket/commit/c24adeb3efd57a18b2f287c35d029e88b5a47194
- https://github.com/fastify/fastify-websocket
- https://github.com/fastify/fastify-websocket/releases/tag/v5.0.1
- https://github.com/fastify/fastify-websocket/releases/tag/v7.1.1
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-248- Platform
- npm
- Package
@fastify/websocket, fastify-websocket- Disclosed
- 07.11.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-4pcg-wr6c-h9cq - CC BY 4.0
Vulnerability history: fastify-websocket
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
This is the only known vulnerability of this package.
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