SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-11941

Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions.

MEDIUM 5.6EPSS 0.25%

Does this matter?

Lower severity and a low EPSS score (0.25%). Track it; it rarely justifies an emergency change on its own.

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 3.1
5.6 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS
0.25% probability · 16th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-416
Source
cna@cloudflare.com
EPSS trend
0%3%5%26 October 2026: 0.25%26 October 202626 October 2026

EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.