CVE-2021-44686

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.88% Top 30%
Vendor Advisory fedoraproject.org Vendor Advisory launchpad.net
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://bugs.launchpad.net/calibre/+bug/1951979 issue tracking exploit vendor advisory
https://github.com/dwisiswant0/advisory/issues/18 issue tracking patch exploit third party advisory
https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0 third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/W7QKFPYJ23KG6WJ5NIYAM4N2NWZCLQGL/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-44686?
CVE-2021-44686 has been scored as a high severity vulnerability.
How to fix CVE-2021-44686?
To fix CVE-2021-44686, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-44686 being actively exploited in the wild?
It is possible that CVE-2021-44686 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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