CVE-2021-28652: Debian Linux

Medium severity, CVSS 4.9. EPSS: 4.3% chance of exploitation in the next 30 days.

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to incorrect parser validation, it allows a Denial of Service attack against the Cache Manager API. This allows a trusted client to trigger memory leaks that. over time, lead to a Denial of Service via an unspecified short query string. This attack is limited to clients with Cache Manager API access privilege.

Affected products

• Debian Debian Linux: version 9.0 only; version 10.0 only
• Fedoraproject Fedora: version 33 only; version 34 only
• Squid-Cache Squid: from 1.0, before 4.15 (fixed in 4.15); from 5.0, before 5.0.6 (fixed in 5.0.6)

Published 2021-05-27. Last modified 2026-06-17.