Use After Free in Squid-cache Squid

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 o…

Vulnerability class: Use-After-Free

EPSS: 0.089 (94.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33526?
CVE-2026-33526 is a high-severity vulnerability in Squid-cache Squid, classified under Use After Free. CVSS score: 7.5/10. Published 2026-03-26.
How severe is CVE-2026-33526?
High severity. CVSS v3 base score is 7.5 out of 10.