HIGH8.7
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.
CVSS 3.xHIGH 7.5
CVSS:3.x/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCVSS 4.0HIGH 8.7
CVSS:4.0/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XReferences
- https://github.com/squid-cache/squid/commit/703e07d25ca6fa11f52d20bf0bb879e22ab7481b
- https://github.com/squid-cache/squid/security/advisories/GHSA-f9p7-3jqg-hhvq
- http://www.openwall.com/lists/oss-security/2026/03/25/3
- https://access.redhat.com/errata/RHSA-2026:10255
- https://access.redhat.com/errata/RHSA-2026:10256
- https://access.redhat.com/errata/RHSA-2026:10257
- https://access.redhat.com/errata/RHSA-2026:11901
- https://access.redhat.com/errata/RHSA-2026:20564
- https://access.redhat.com/errata/RHSA-2026:20565
- https://access.redhat.com/errata/RHSA-2026:20580
- https://access.redhat.com/errata/RHSA-2026:6301
- https://access.redhat.com/errata/RHSA-2026:8119
- https://access.redhat.com/errata/RHSA-2026:8317
- https://access.redhat.com/errata/RHSA-2026:8880
- https://access.redhat.com/errata/RHSA-2026:9220
- https://access.redhat.com/security/cve/CVE-2026-32748
- https://bugzilla.redhat.com/show_bug.cgi?id=2451577
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32748.json