CVE-2021-44686: High severity calibre vulnerability

Published Dec 6, 2021
·
Updated

calibre before 5.32.0 contains a regular expression that is vulnerable to ReDoS (Regular Expression Denial of Service) in htmlpreprocessrules in ebooks/conversion/preprocess.py.

Affected Software

2 affected components
Calibre-ebook Calibre<5.32.0
Fedoraproject Fedora=34

Event History

Dec 6, 2021
CVE Published
via MITRE·11:41 PM
Data Sourced
via MITRE·11:41 PM
Description
Dec 7, 2021
Data Sourced
via NVD·12:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-44686?

CVE-2021-44686 is a vulnerability found in calibre before version 5.32.0, which can be exploited through a regular expression denial of service (ReDoS) attack.

2

What is ReDoS?

ReDoS stands for Regular Expression Denial of Service, which is a vulnerability that occurs when a regular expression takes an exceptionally long time to evaluate certain input.

3

How does CVE-2021-44686 affect calibre?

CVE-2021-44686 affects calibre versions before 5.32.0 and specifically impacts the html_preprocess_rules functionality in ebooks/conversion/preprocess.py.

4

What is the severity level of CVE-2021-44686?

CVE-2021-44686 has a severity level of 7.5 (High).

5

How can I fix CVE-2021-44686?

To fix CVE-2021-44686, it is recommended to update calibre to version 5.32.0 or later.

Contact

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