CVE-2026-55213
- Source
- https://cve.org/CVERecord?id=CVE-2026-55213
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55213.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-55213
- Aliases
-
- GHSA-432c-8xmj-frmq
- Downstream
- Published
- 2026-07-10T20:49:58.764Z
- Modified
- 2026-07-16T03:31:00.206677665Z
- Severity
-
- 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- h2o: musl libc stack overflow (QPACK)
- Details
-
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1, when h2o processes a QPACK instruction sent from the peer over HTTP/3, lib/http3/qpack.c might allocate an on-stack buffer as large as approximately 800 KB by calling alloca, which exceeds the default pthread stack size used by musl libc and causes the h2o server to crash with a segmentation fault while touching the guard page. This issue is fixed in commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1.
- Database specific
{ "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55213.json", "cwe_ids": [ "CWE-789" ], "cna_assigner": "GitHub_M", "unresolved_ranges": [ { "source": "AFFECTED_FIELD", "extracted_events": [ { "fixed": "edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1" } ] } ] }- References
Affected packages
Git / github.com/h2o/h2o
Affected versions
v0.*
v0.9.1
v0.9.2
v1.*
v1.0.1
v1.1.0
v1.1.1
v1.2.0
v1.3.0
v1.3.0-beta1
v1.3.1
v1.4.0
v1.4.1
v1.4.2
v1.5.0
v1.5.0-beta1
v1.5.0-beta2
v1.5.0-beta3
v1.5.0-beta4
v1.5.1
v1.5.2
v1.5.3
v1.6.0
v1.6.0-beta1
v1.6.0-beta2
v1.7.0
v1.7.0-beta1
v1.7.0-beta2
v1.7.0-beta3
v1.7.0-beta4
v1.7.0-beta5