CVE-2026-27135
Last modified
CVE-2026-27135 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. nghttp2 is an implementation of the Hypertext Transfer Protocol version 2 in C. Prior to version 1.68.1, the nghttp2 library stops reading the incoming data when user facing public API `nghttp2_session_terminate_session` or `nghttp2_session_terminate_session2` is called by the application. EPSS estimates a 0.56% chance of exploitation in the next 30 days.
Description
nghttp2 is an implementation of the Hypertext Transfer Protocol version 2 in C. Prior to version 1.68.1, the nghttp2 library stops reading the incoming data when user facing public API `nghttp2_session_terminate_session` or `nghttp2_session_terminate_session2` is called by the application. They might be called internally by the library when it detects the situation that is subject to connection error. Due to the missing internal state validation, the library keeps reading the rest of the data after one of those APIs is called. Then receiving a malformed frame that causes FRAME_SIZE_ERROR causes assertion failure. nghttp2 v1.68.1 adds missing state validation to avoid assertion failure. No known workarounds are available.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Nghttp2 | Nghttp2 | < 1.68.1 |
References
- https://github.com/nghttp2/nghttp2/security/advisories/GHSA-6933-cjhr-5qg6Patch, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/03/20/3Mailing List, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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