Use After Free Affecting squid package, versions <7:5.5-22.el9_7.4


Severity

Recommended
0.0
high
0
10

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
1.7% (83rd percentile)

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  • Snyk IDSNYK-ALMALINUX9-SQUID-15909853
  • published5 Apr 2026
  • disclosed31 Mar 2026

Introduced: 31 Mar 2026

NewCVE-2026-33526  (opens in a new tab)
CWE-416  (opens in a new tab)
CWE-826  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:9 squid to version 7:5.5-22.el9_7.4 or higher.
This issue was patched in ALSA-2026:6301.

NVD Description

Note: Versions mentioned in the description apply only to the upstream squid package and not the squid package as distributed by AlmaLinux. See How to fix? for AlmaLinux:9 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1