← CVE Intelligence

CVE-2026-27135

nghttp2 Denial of service: Assertion failure due to the missing state validation PUBLISHED

Description (CNA)

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.

Affected (CNA)

Vendor / productVersions
nghttp2 / nghttp2affected < 1.68.1

CWE

CWE-617

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

CVE

No English description supplied.

redhat-SADP

A flaw was found in nghttp2. Due to missing internal state validation, the library continues to process incoming data even after a session has been terminated. A remote attacker could exploit this by sending a specially crafted HTTP/2 frame, leading to an assertion failure and a denial of service (DoS).

siemens-SADP

No English description supplied.