CVE WatchJul 15, 2026

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 handli

CVSS

7.5

High

EPSS

8.9%

p95

KEV

—

Exploit Today

0-100

Published: Mar 26, 2026 · Last modified: Jul 15, 2026 · CWE-416 · CWE-826 · CWE-825

EPSS · 30d

8.9%EPSS · 30 days8.9%

2026-06-302026-07-16

Technical 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.

Official references

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