Vulnerability · Published Dec 6, 2021 · Assigned by mitre
CVE-2021-44686
High 7.5
In plain English
A high-severity security flaw in the calibre package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 5.2% (higher than 93% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)7.5High
Exploit odds (30 days)5.2%top 7.5% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | calibre | 5.33.0+dfsg-1 | DEBIAN-CVE-2021-44686 |
| Debian:13 | calibre | 5.33.0+dfsg-1 | DEBIAN-CVE-2021-44686 |
| Debian:14 | calibre | 5.33.0+dfsg-1 | DEBIAN-CVE-2021-44686 |
| Ubuntu:22.04:LTS | calibre | no fix listed | UBUNTU-CVE-2021-44686 |
| Ubuntu:26.04:LTS | calibre | no fix listed | UBUNTU-CVE-2021-44686 |
Affected products (as reported)
References
- https://bugs.launchpad.net/calibre/+bug/1951979 x_refsource_MISC
- https://github.com/dwisiswant0/advisory/issues/18 x_refsource_MISC
- https://github.com/kovidgoyal/calibre/compare/v5.31.1...v5.32.0 x_refsource_MISC
- FEDORA-2021-e42fadbcc3 vendor-advisory, x_refsource_FEDORA
- https://lists.debian.org/debian-lts-announce/2024/09/msg00005.html