{"id":"CVE-2021-33620","details":"Squid before 4.15 and 5.x before 5.0.6 allows remote servers to cause a denial of service (affecting availability to all clients) via an HTTP response. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent by the server.","modified":"2026-02-24T11:42:59.920075Z","published":"2021-05-28T12:15:07.697Z","related":["ALSA-2021:4292","GHSA-572g-rvwr-6c7f","MGASA-2021-0237","SUSE-SU-2022:2367-1","SUSE-SU-2022:2553-1","openSUSE-SU-2024:11929-1"],"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LSQ3U54ZCNXR44QRPW3AV2VCS6K3TKCF/"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T4EPIWUZDJAXADDHVOPKRBTQHPBR6H66/"},{"type":"ADVISORY","url":"http://seclists.org/fulldisclosure/2023/Oct/14"},{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2023/10/11/3"},{"type":"ADVISORY","url":"http://www.squid-cache.org/Versions/v4/changesets/squid-4-1e05a85bd28c22c9ca5d3ac9f5e86d6269ec0a8c.patch"},{"type":"ADVISORY","url":"http://www.squid-cache.org/Versions/v5/changesets/squid-5-8af775ed98bfd610f9ce762fe177e01b2675588c.patch"},{"type":"ADVISORY","url":"https://github.com/squid-cache/squid/security/advisories/GHSA-572g-rvwr-6c7f"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html"},{"type":"FIX","url":"http://www.squid-cache.org/Versions/v4/changesets/squid-4-1e05a85bd28c22c9ca5d3ac9f5e86d6269ec0a8c.patch"},{"type":"FIX","url":"http://www.squid-cache.org/Versions/v5/changesets/squid-5-8af775ed98bfd610f9ce762fe177e01b2675588c.patch"},{"type":"FIX","url":"https://github.com/squid-cache/squid/security/advisories/GHSA-572g-rvwr-6c7f"},{"type":"ARTICLE","url":"http://seclists.org/fulldisclosure/2023/Oct/14"},{"type":"ARTICLE","url":"http://www.openwall.com/lists/oss-security/2023/10/11/3"},{"type":"ARTICLE","url":"http://www.squid-cache.org/Versions/v4/changesets/squid-4-1e05a85bd28c22c9ca5d3ac9f5e86d6269ec0a8c.patch"},{"type":"ARTICLE","url":"http://www.squid-cache.org/Versions/v5/changesets/squid-5-8af775ed98bfd610f9ce762fe177e01b2675588c.patch"},{"type":"ARTICLE","url":"https://lists.debian.org/debian-lts-announce/2021/06/msg00014.html"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git","events":[{"introduced":"0"},{"fixed":"d8a5b80568a9cb66810e75b182018e9edb68e8ff"}]}],"versions":["v2.6.12","v2.6.12-rc2","v2.6.12-rc3","v2.6.12-rc4","v2.6.12-rc5","v2.6.12-rc6","v2.6.13","v2.6.13-rc1","v2.6.13-rc2","v2.6.13-rc3","v2.6.13-rc4","v2.6.13-rc5","v2.6.13-rc6","v2.6.13-rc7","v2.6.14","v2.6.14-rc1","v2.6.14-rc2","v2.6.14-rc3","v2.6.14-rc4","v2.6.14-rc5","v2.6.15","v2.6.15-rc1","v2.6.15-rc2","v2.6.15-rc3","v2.6.15-rc4","v2.6.15-rc5","v2.6.15-rc6","v2.6.15-rc7","v2.6.16","v2.6.16-rc1","v2.6.16-rc2","v2.6.16-rc3","v2.6.16-rc4","v2.6.16-rc5","v2.6.16-rc6","v2.6.17","v2.6.17-rc1","v2.6.17-rc2","v2.6.17-rc3","v2.6.17-rc4","v2.6.17-rc5","v2.6.17-rc6","v2.6.18","v2.6.18-rc1","v2.6.18-rc2","v2.6.18-rc3","v2.6.18-rc4","v2.6.18-rc5","v2.6.18-rc6","v2.6.18-rc7","v2.6.19","v2.6.19-rc1","v2.6.19-rc2","v2.6.19-rc3","v2.6.19-rc4","v2.6.19-rc5","v2.6.19-rc6","v2.6.20","v2.6.20-rc1","v2.6.20-rc2","v2.6.20-rc3","v2.6.20-rc4","v2.6.20-rc5","v2.6.20-rc6","v2.6.20-rc7","v2.6.21","v2.6.21-rc1","v2.6.21-rc2","v2.6.21-rc3","v2.6.21-rc4","v2.6.21-rc5","v2.6.21-rc6","v2.6.21-rc7","v2.6.22","v2.6.22-rc1","v2.6.22-rc2","v2.6.22-rc3","v2.6.22-rc4","v2.6.22-rc5","v2.6.22-rc6","v2.6.22-rc7","v2.6.23","v2.6.23-rc1","v2.6.23-rc2","v2.6.23-rc3","v2.6.23-rc4","v2.6.23-rc5","v2.6.23-rc6","v2.6.23-rc7","v2.6.23-rc8","v2.6.23-rc9","v2.6.24","v2.6.24-rc1","v2.6.24-rc2","v2.6.24-rc3","v2.6.24-rc4","v2.6.24-rc5","v2.6.24-rc6","v2.6.24-rc7","v2.6.24-rc8","v2.6.25","v2.6.25-rc1","v2.6.25-rc2","v2.6.25-rc3","v2.6.25-rc4","v2.6.25-rc5","v2.6.25-rc6","v2.6.25-rc7","v2.6.25-rc8","v2.6.25-rc9","v2.6.26","v2.6.26-rc1","v2.6.26-rc2","v2.6.26-rc3","v2.6.26-rc4","v2.6.26-rc5","v2.6.26-rc6","v2.6.26-rc7","v2.6.26-rc8","v2.6.26-rc9","v2.6.27","v2.6.27-rc1","v2.6.27-rc2","v2.6.27-rc3","v2.6.27-rc4","v2.6.27-rc5","v2.6.27-rc6","v2.6.27-rc7","v2.6.27-rc8","v2.6.27-rc9","v2.6.28","v2.6.28-rc1","v2.6.28-rc2","v2.6.28-rc3","v2.6.28-rc4","v2.6.28-rc5","v2.6.28-rc6","v2.6.28-rc7","v2.6.28-rc8","v2.6.28-rc9","v2.6.29","v2.6.29-rc1","v2.6.29-rc2","v2.6.29-rc3","v2.6.29-rc4","v2.6.29-rc5","v2.6.29-rc6","v2.6.29-rc7","v2.6.29-rc8","v2.6.30","v2.6.30-rc1","v2.6.30-rc2","v2.6.30-rc3","v2.6.30-rc4","v2.6.30-rc5","v2.6.30-rc6","v2.6.30-rc7","v2.6.30-rc8","v2.6.31","v2.6.31-rc1","v2.6.31-rc2","v2.6.31-rc3","v2.6.31-rc4","v2.6.31-rc5","v2.6.31-rc6","v2.6.31-rc7","v2.6.31-rc8","v2.6.31-rc9","v2.6.32","v2.6.32-rc1","v2.6.32-rc2","v2.6.32-rc3","v2.6.32-rc4","v2.6.32-rc5","v2.6.32-rc6","v2.6.32-rc7","v2.6.32-rc8","v2.6.33","v2.6.33-rc1","v2.6.33-rc2","v2.6.33-rc3","v2.6.33-rc4","v2.6.33-rc5","v2.6.33-rc6","v2.6.33-rc7","v2.6.33-rc8","v2.6.34","v2.6.34-rc1","v2.6.34-rc2","v2.6.34-rc3","v2.6.34-rc4","v2.6.34-rc5","v2.6.34-rc6","v2.6.34-rc7","v2.6.35","v2.6.35-rc1","v2.6.35-rc2","v2.6.35-rc3","v2.6.35-rc4","v2.6.35-rc5","v2.6.35-rc6","v2.6.36","v2.6.36-rc1",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