calibre before 5.32.0 contains a regular expression that is vulnerable...

7.5 CVSS

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

More from calibre-ebook

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CVE-2018-7889

gui2/viewer/bookmarkmanager.py in Calibre 3.18 calls cPickle.load on imported bookmark data,...

High 7.8

CVE-2016-10187

The E-book viewer in calibre before 2.75 allows remote attackers...

Medium 5.5

Affected Vendor

calibre-ebook

View all reports →

Affected Software

calibre, fedora

Vulnerable Versions:

0, 34

Timeline

Official Publish: December 6th, 2021

Last Modified: November 4th, 2025

Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.