Vulnerability Description
Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions. The “quiche_connection_id_iter_next” and “quiche_conn_retired_scid_next” functions would return a pointer to a “ConnectionId” to the applications via function arguments, but the owned “ConnectionId” would be dropped at the end of those functions' scope. Only applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag. Impact If unpatched, an application calling the affected FFI functions will dereference freed memory. The most likely outcome is undefined behavior leading to a process crash (denial of service). Depending on allocator state, the read may also return adjacent heap contents, resulting in limited information disclosure or incorrect connection identifier handling. Mitigation Users are requested to upgrade to quiche 0.29.2 which is the earliest version containing the fix for this issue.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
FAQ
What is CVE-2026-11941?
CVE-2026-11941 is a vulnerability with a CVSS score of 5.6 (MEDIUM). Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions. The “quiche_connection_id_iter_next” and “quiche_conn_retired_scid_next” functions wo...
How severe is CVE-2026-11941?
CVE-2026-11941 has been rated MEDIUM with a CVSS base score of 5.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-11941?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.