Name: CVE-2021-44686: Uncontrolled Resource Consumption
Creator: Rapid7
Published: 2021-12-06T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-44686, CWE-400, CVSS 7.5, EPSS 0.00412

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 Details

CVSS 3.1 Base Score: 7.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade calibre	Jul 30, 2024	Dec 7, 2021
Ubuntu	—	No solution exists	Jun 26, 2025	Dec 7, 2021

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence