CVE-2026-27135
HIGH EPSS 42.4%
Published Mar 18, 20263mo ago · Modified May 13, 20261mo ago
7.5 CVSS 3.1
Published Mar 18, 2026 3mo ago
Last Modified May 13, 2026 1mo ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High
Threat Intelligence
EPSS Exploit Probability
42.4% percentile
Exploit & Patch Status
No Known Exploit
Patch Available
Weaknesses 1
CWE-617
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| nghttp2 | nghttp2 | * | <1.68.1 |
References 4
- openwall.com http://www.openwall.com/lists/oss-security/2026/03/20/3
- github.com https://github.com/nghttp2/nghttp2/commit/5c7df8fa815ac1004d9ecb9d1f7595c4d37f46e1
- github.com https://github.com/nghttp2/nghttp2/security/advisories/GHSA-6933-cjhr-5qg6
- lists.debian.org https://lists.debian.org/debian-lts-announce/2026/05/msg00025.html
Remediation
- github.com https://github.com/nghttp2/nghttp2/commit/5c7df8fa815ac1004d9ecb9d1f7595c4d37f46e1
- github.com https://github.com/nghttp2/nghttp2/security/advisories/GHSA-6933-cjhr-5qg6