High severity7.5NVD Advisory· Published Jul 17, 2026· Updated Aug 5, 2026
CVE-2026-54340
CVE-2026-54340
Description
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 9265bdd, there is an HTTP/2 state amplification issue that combines HPACK decompression amplification with Slowloris-style stream stalling. Amplified decoded header state can be retained by stalled HTTP/2 streams, and depending on the configuration, additional limits are needed to bound decoded header state and prevent attack. This issue has been fixed by commit 9265bdd.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
1Patches
Vulnerability mechanics
References
2- github.com/h2o/h2o/commit/9265bdd9a996ed992681055e3996baf3e09d2063nvdPatch
- github.com/h2o/h2o/security/advisories/GHSA-qcrr-wrhc-pgq9nvdThird Party Advisory
News mentions
0No linked articles in our index yet.