DEBIAN-CVE-2026-55213

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Source
https://security-tracker.debian.org/tracker/CVE-2026-55213
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55213.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-55213
Upstream
Published
2026-07-10T21:16:55Z
Modified
2026-09-14T17:03:19Z
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
[none]
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.

References

Affected packages

Debian:12 / h2o

Package

Name
h2o
Purl
pkg:deb/debian/h2o?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.2.5+dfsg2-7
2.2.5+dfsg2-8
2.2.5+dfsg2-8.1~exp1
2.2.5+dfsg2-8.1
2.2.5+dfsg2-9
2.2.5+dfsg2-10
2.2.5+dfsg2-11

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55213.json"