CVE-2021-44686

7.5 HIGH

Published: December 07, 2021 Modified: November 04, 2025

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0

Vector String

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory

https://bugs.launchpad.net/calibre/+bug/1951979

Source: cve@mitre.org

Exploit Issue Tracking Vendor Advisory

https://github.com/dwisiswant0/advisory/issues/18

Source: cve@mitre.org

Exploit Issue Tracking Patch Third Party Advisory

https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0

Source: cve@mitre.org

Patch Third Party Advisory

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/

Source: cve@mitre.org

https://bugs.launchpad.net/calibre/+bug/1951979