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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/nghttp2/nghttp2/commit/5c7df8fa815ac1004d9ecb9d1f7595c4d37f46e1 Patch
- https://github.com/nghttp2/nghttp2/security/advisories/GHSA-6933-cjhr-5qg6 Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.5 · nghttp2NVD modified 2026-10-15 02:18
Affected (CPE criteria) 1
cpe:2.3:a:nghttp2:nghttp2:*:*:*:*:*:*:*:*
References 56
- https://github.com/nghttp2/nghttp2/commit/5c7df8fa815ac1004d9ecb9d1f7595c4d37f46e1 Patch
- https://github.com/nghttp2/nghttp2/security/advisories/GHSA-6933-cjhr-5qg6 Patch, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/03/20/3 Mailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2026/05/msg00025.html
- https://access.redhat.com/errata/RHSA-2026:10065
- https://access.redhat.com/errata/RHSA-2026:11768
- https://access.redhat.com/errata/RHSA-2026:13812
- https://access.redhat.com/errata/RHSA-2026:14773
- https://access.redhat.com/errata/RHSA-2026:14937
- https://access.redhat.com/errata/RHSA-2026:15087
- https://access.redhat.com/errata/RHSA-2026:16008
- https://access.redhat.com/errata/RHSA-2026:16009
- https://access.redhat.com/errata/RHSA-2026:16030
- https://access.redhat.com/errata/RHSA-2026:16174
- https://access.redhat.com/errata/RHSA-2026:17596
- https://access.redhat.com/errata/RHSA-2026:19724
- https://access.redhat.com/errata/RHSA-2026:19725
- https://access.redhat.com/errata/RHSA-2026:20040
- https://access.redhat.com/errata/RHSA-2026:20087
- https://access.redhat.com/errata/RHSA-2026:21656
- https://access.redhat.com/errata/RHSA-2026:21690
- https://access.redhat.com/errata/RHSA-2026:21695
- https://access.redhat.com/errata/RHSA-2026:25096
- https://access.redhat.com/errata/RHSA-2026:27200
- https://access.redhat.com/errata/RHSA-2026:27201
- https://access.redhat.com/errata/RHSA-2026:6190
- https://access.redhat.com/errata/RHSA-2026:7080
- https://access.redhat.com/errata/RHSA-2026:7123
- https://access.redhat.com/errata/RHSA-2026:7302
- https://access.redhat.com/errata/RHSA-2026:7310
- https://access.redhat.com/errata/RHSA-2026:7350
- https://access.redhat.com/errata/RHSA-2026:7666
- https://access.redhat.com/errata/RHSA-2026:7667
- https://access.redhat.com/errata/RHSA-2026:7668
- https://access.redhat.com/errata/RHSA-2026:7670
- https://access.redhat.com/errata/RHSA-2026:7675
- https://access.redhat.com/errata/RHSA-2026:7896
- https://access.redhat.com/errata/RHSA-2026:7983
- https://access.redhat.com/errata/RHSA-2026:8339
- https://access.redhat.com/errata/RHSA-2026:8538
- https://access.redhat.com/errata/RHSA-2026:8539
- https://access.redhat.com/errata/RHSA-2026:8540
- https://access.redhat.com/errata/RHSA-2026:8541
- https://access.redhat.com/errata/RHSA-2026:8545
- https://access.redhat.com/errata/RHSA-2026:8546
- https://access.redhat.com/errata/RHSA-2026:8547
- https://access.redhat.com/errata/RHSA-2026:8548
- https://access.redhat.com/errata/RHSA-2026:8868
- https://access.redhat.com/errata/RHSA-2026:9711
- https://access.redhat.com/errata/RHSA-2026:9832
- https://access.redhat.com/errata/RHSA-2026:9874
- https://access.redhat.com/security/cve/CVE-2026-27135
- https://bugzilla.redhat.com/show_bug.cgi?id=2448754
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27135.json