CVE-2026-33526

HIGH

Squid vulnerable to Denial of Service in ICP Request handling

Title source: cna
STIX 2.1

Description

Squid is a caching proxy for the Web. Prior to version 7.5, due to heap Use-After-Free, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker to perform a reliable and repeatable Denial of Service attack against the Squid service using ICP protocol. This attack is limited to Squid deployments that explicitly enable ICP support (i.e. configure non-zero `icp_port`). This problem _cannot_ be mitigated by denying ICP queries using `icp_access` rules. Version 7.5 contains a patch.

Scores

CVSS v3 7.5
EPSS 0.0214
EPSS Percentile 84.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-416 CWE-826
Status published
Products (1)
squid-cache/squid < 7.5 (2 CPE variants)
Published Mar 26, 2026
Tracked Since Mar 26, 2026