{"id":"CVE-2021-44686","aliases":["DEBIAN-CVE-2021-44686","DLA-3862-1","EUVD-2021-31502","GHSA-m6m7-mf2p-99p5","MGASA-2021-0593","UBUNTU-CVE-2021-44686"],"status":"published","title":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular...","description":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in 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Tracking","Vendor Advisory","report"]},{"url":"https://github.com/dwisiswant0/advisory/issues/18","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Patch","Third Party Advisory","fix","report"]},{"url":"https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://lists.debian.org/debian-lts-announce/2024/09/msg00005.html","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-44686"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/"},{"url":"https://github.com/advisories/GHSA-m6m7-mf2p-99p5"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-44686","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2021-0593.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=29803","tags":["report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/thread/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2021-44686","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-44686","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-44686","description":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.","status":"published","published":"2021-12-06T23:41:12Z","modified":"2025-11-04T16:09:27.961Z","updated_at":"2026-11-02T14:33:00.819444Z"}],"euvd":[{"id":"EUVD-2021-31502","description":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.","status":"published","published":"2021-12-06T23:41:12Z","modified":"2025-11-04T16:09:27Z","updated_at":"2026-11-02T19:49:29.391161Z"}],"ghsa":[{"id":"GHSA-m6m7-mf2p-99p5","title":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular...","description":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.","status":"published","published":"2021-12-08T00:01:44Z","modified":"2023-02-01T05:07:01Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-400","CWE-770"],"updated_at":"2026-11-02T14:50:27.906349Z"}],"nvd":[{"id":"CVE-2021-44686","description":"calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.","status":"published","published":"2021-12-07T00:15:08.087Z","modified":"2026-06-17T04:12:41.52Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:07:01.811115Z"}],"osv":[{"id":"CVE-2021-44686","description":"calibre before 5.32.0 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that is vulnerable to ReDoS (Regular Expression Denial of Service) in html_preprocess_rules in ebooks/conversion/preprocess.py.","status":"published","published":"2021-12-07T00:15:00Z","modified":"2026-05-20T16:05:20.586193063Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:29.220315Z"},{"id":"DLA-3862-1","title":"calibre - security update","status":"published","published":"2024-09-02T00:00:00Z","modified":"2026-03-09T01:17:52.464031Z","updated_at":"2026-11-02T15:46:12.203458Z"},{"id":"MGASA-2021-0593","title":"Updated calibre packages fix security vulnerability","description":"ReDoS vulnerability in html_preprocess_rules\nin ebooks/conversion/preprocess.py\n","status":"published","published":"2021-12-30T16:41:51Z","modified":"2026-04-16T04:44:01.17844866Z","updated_at":"2026-11-02T15:49:41.849028Z"}]}}