Summary
Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: 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. NOTE: https://www.openwall.com/lists/oss-security/2026/03/25/2 NOTE: Fixed by: https://github.com/squid-cache/squid/commit/8a7d42f9d44befb8fcbbb619505587c8de6a1e91 (SQUID_7_5) CVE-2026-32748: Squid is a caching proxy for the Web. Prior to version 7.5, due to premature release of resource during expected lifetime and heap Use-After-Free bugs, 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. This bug is fixed in Squid version 7.5. NOTE: https://www.openwall.com/lists/oss-security/2026/03/25/3 NOTE: Fixed by: https://github.com/squid-cache/squid/commit/703e07d25ca6fa11f52d20bf0bb879e22ab7481b (SQUID_7_5)
Fixed packages 4
| Release | Package | Fixed in |
|---|---|---|
| Amazon Linux · 2 | squid | 7:3.5.20-17.amzn2.7.26 |
| Amazon Linux · 2 | squid-debuginfo | 7:3.5.20-17.amzn2.7.26 |
| Amazon Linux · 2 | squid-migration-script | 7:3.5.20-17.amzn2.7.26 |
| Amazon Linux · 2 | squid-sysvinit | 7:3.5.20-17.amzn2.7.26 |
Vulnerabilities 2
-
Critical 9.2
Squid vulnerable to Denial of Service in ICP Request handling
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 aga…
-
High 8.7
Squid has Denial of Service in ICP Response handling
Squid is a caching proxy for the Web. Prior to version 7.5, due to premature release of resource during expected lifetime and heap Use-After-Free bugs, Squid is vulnerable to Denial of Service when handling ICP traffic. This problem allows a remote attacker t…