{"id":"CVE-2026-32748","state":"PUBLISHED","title":"Squid has Denial of Service in ICP Response handling","description":"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.","publishedAt":"2026-03-26T00:11:01.424Z","updatedAt":"2026-07-15T01:07:40.483Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["squid-cache squid"],"affected":[{"vendor":"squid-cache","product":"squid","versions":[{"version":"< 7.5","status":"affected"}]}],"references":["https://github.com/squid-cache/squid/security/advisories/GHSA-f9p7-3jqg-hhvq","https://github.com/squid-cache/squid/commit/703e07d25ca6fa11f52d20bf0bb879e22ab7481b","http://www.openwall.com/lists/oss-security/2026/03/25/3","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","https://access.redhat.com/errata/RHSA-2026:8880","https://access.redhat.com/errata/RHSA-2026:11901","https://access.redhat.com/errata/RHSA-2026:8119","https://access.redhat.com/errata/RHSA-2026:8317","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-2026:10256","https://access.redhat.com/errata/RHSA-2026:10257","https://access.redhat.com/errata/RHSA-2026:10255","https://access.redhat.com/errata/RHSA-2026:9220","https://access.redhat.com/errata/RHSA-2026:6301"],"weaknesses":["CWE-413","CWE-416","CWE-826"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/32xxx/CVE-2026-32748.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-32748","state":"PUBLISHED","datePublished":"2026-03-26T00:11:01.424Z","dateUpdated":"2026-07-15T01:07:40.483Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-13T18:53:03.531Z"},"containers":{"cna":{"title":"Squid has Denial of Service in ICP Response handling","descriptions":[{"lang":"en","value":"Squid is a caching proxy for the Web. 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A remote attacker can exploit this vulnerability by sending specially crafted ICP (Internet Cache Protocol) traffic. This can lead to a Denial of Service (DoS) due to premature resource release and use-after-free vulnerabilities. This attack is possible in Squid deployments with explicitly enabled ICP support."}],"affected":[{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","packageName":"squid","defaultStatus":"affected","versions":[{"version":"7:6.10-6.el10_1.3","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:10.1"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10.0 Extended Update Support","packageName":"squid","defaultStatus":"affected","versions":[{"version":"7:6.10-5.el10_0.2","status":"unaffected","lessThan":"*","versionType":"rpm"}],"collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux_eus:10.0"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7 Extended Lifecycle 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9)"}],"timeline":[{"lang":"en","time":"2026-03-26T01:01:29.920Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-03-26T00:11:01.424Z","value":"Made public."}],"workarounds":[{"lang":"en","value":"To mitigate this issue, ensure that ICP support is not explicitly enabled in the Squid configuration. This can be achieved by commenting out or setting `icp_port` to `0` in the `squid.conf` file. After modifying the configuration, the Squid service must be reloaded or restarted for the changes to take effect.\n\nExample:\n```\n# icp_port 3130\n```\nor\n```\nicp_port 0\n```\nWarning: Reloading or restarting the Squid service may temporarily interrupt proxy services."}],"x_adpType":"supplier","x_generator":{"engine":"sadp-cli 1.0.0"}}]}}}