CVE-2022-39386: fastify fastify-websocket Uncaught Exception
Vulnerability summary
CVE-2022-39386 is a high (CVSS 7.5) Uncaught Exception vulnerability in fastify fastify-websocket. EPSS estimates a 0.80% chance of exploitation in the next 30 days, higher than 55.6% of scored vulnerabilities.
Timeline
- 08-11-2022PublishedVulnerability first disclosed.
- 23-04-2025Last modifiedVulnerability information updated.
Description
@fastify/websocket provides WebSocket support for Fastify. 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. This has been patched in version 7.1.1 (fastify v4) and version 5.0.1 (fastify v3). There are currently no known workarounds. However, it should be possible to attach the error handler manually. The recommended path is upgrading to the patched versions.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · NpmEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.80%
Chance of exploitation in the next 30 days
Percentile
56%
Versus all other CVEs
30-day change
+0.02 pp
From 0.78% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Fastify2 products
- fastify-websocket≥ 5.0.0, < 5.0.1 | ≥ 6.0.0, < 7.1.1 | ≤ 4.3.0
- websocket≥ 6.0.0, < 7.1.1 | 5.0.0
@fastify1 product
- websocket≥ 5.0.0, < 5.0.1 | ≥ 6.0.0, < 7.1.1
Npm1 product
- fastify-websocket≤ 4.3.0
3 vendors · 4 products
