CVE-2026-33526

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

No CVSS.

References

Link	Resource
https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91
https://github.com/squid-cache/squid/security/advisories/GHSA-hpfx-h48q-gvwg
http://www.openwall.com/lists/oss-security/2026/03/25/2

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-26 01:16

Updated : 2026-03-26 15:13

NVD link : CVE-2026-33526

Mitre link : CVE-2026-33526

CVE.ORG link : CVE-2026-33526

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

CWE-826

Premature Release of Resource During Expected Lifetime

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