VulnerabilityModified
CVE-2021-44686
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.
HIGH 7.5EPSS 4.99%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (4.99%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 4.99% probability · 92th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- calibre-ebook/calibre · fedoraproject/fedora
- Source
- cve@mitre.org
References
- https://bugs.launchpad.net/calibre/+bug/1951979Exploit, Issue Tracking, Vendor Advisory
- https://github.com/dwisiswant0/advisory/issues/18Exploit, Issue Tracking, Patch, Third Party Advisory
- https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/
- https://bugs.launchpad.net/calibre/+bug/1951979Exploit, Issue Tracking, Vendor Advisory
- https://github.com/dwisiswant0/advisory/issues/18Exploit, Issue Tracking, Patch, Third Party Advisory
- https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2024/09/msg00005.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.