What is CVE-2026-11941?

CVE-2026-11941 is a medium-severity vulnerability in Cloudflare Quiche, classified under Use After Free. CVSS score: 5.6/10. Published 2026-06-19.

How severe is CVE-2026-11941?

Medium severity. CVSS v3 base score is 5.6 out of 10.

Use After Free in Cloudflare Quiche

CVE-2026-11941

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…

Vulnerability class: Use-After-Free

CVSS v3 metric

CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Cloudflare Quiche — versions 0.20.0

Weakness classification (CWE)

CWE-416 — Use After Free

References

cna@cloudflare.com

Frequently asked questions

What is CVE-2026-11941?: CVE-2026-11941 is a medium-severity vulnerability in Cloudflare Quiche, classified under Use After Free. CVSS score: 5.6/10. Published 2026-06-19.
How severe is CVE-2026-11941?: Medium severity. CVSS v3 base score is 5.6 out of 10.