{"id":"CVE-2021-41611","aliases":["ALPINE-CVE-2021-41611","DEBIAN-CVE-2021-41611","EUVD-2021-28625","GHSA-47m4-g3mv-9q5r"],"status":"published","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.02948,"percentile":0.87356,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-295"],"published":"2021-10-18T08:56:16Z","modified":"2026-10-23T18:04:15Z","fixes":[{"ecosystem":"Alpine:v3.13","package":"squid","fixed_in":["5.0.6-r2"],"sources":["osv"]},{"ecosystem":"Alpine:v3.14","package":"squid","fixed_in":["5.0.6-r2"],"sources":["osv"]},{"ecosystem":"Alpine:v3.15","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.16","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.17","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.18","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.19","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.20","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.21","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.22","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.23","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"squid","fixed_in":["5.2-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"squid","fixed_in":["5.2-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"squid","fixed_in":["5.2-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"squid","fixed_in":["5.2-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.13","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.0.6-r2"}]}]},{"source":"osv","ecosystem":"Alpine:v3.14","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.0.6-r2"}]}]},{"source":"osv","ecosystem":"Alpine:v3.15","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.16","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.17","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.18","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.19","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.20","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.21","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.22","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.6"},{"fixed":"5.2-r0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.2-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.2-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"squid","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.2-1"}]}]}],"products":[{"vendor":"fedoraproject","product":"fedora"},{"vendor":"squid-cache","product":"squid"}],"references":[{"url":"http://www.squid-cache.org/Versions/v6/changesets/squid-6-43d6b5c81b88ec2256b430c69a872a1e4f324e4a.patch","tags":["x_refsource_MISC","x_transferred","Vendor Advisory","advisory"]},{"url":"https://github.com/squid-cache/squid/security/advisories/GHSA-47m4-g3mv-9q5r","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CWQ2WKDWTSO47S3F6XJJ6HGG2ULWEAE4/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"http://www.openwall.com/lists/oss-security/2021/12/23/2","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://security.alpinelinux.org/vuln/CVE-2021-41611","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-41611","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-41611","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T08:56:16Z","modified":"2024-08-04T03:15:29.048Z","updated_at":"2026-11-02T14:32:59.105382Z"}],"euvd":[{"id":"EUVD-2021-28625","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T08:56:16Z","modified":"2024-08-04T03:15:29Z","updated_at":"2026-11-03T03:24:17.663217Z"}],"nvd":[{"id":"CVE-2021-41611","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T09:15:08.823Z","modified":"2026-06-17T04:08:43.33Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-295"],"updated_at":"2026-11-02T14:06:59.689345Z"}],"osv":[{"id":"ALPINE-CVE-2021-41611","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T09:15:08.823Z","modified":"2026-10-23T17:17:56.214454002Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:27:48.646074Z"},{"id":"CVE-2021-41611","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T09:15:08.823Z","modified":"2026-10-20T10:54:01.352612338Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:21.557945Z"},{"id":"DEBIAN-CVE-2021-41611","description":"An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.","status":"published","published":"2021-10-18T09:15:08.823Z","modified":"2026-10-23T18:04:15.772827049Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:35.799676Z"}]}}