CVE-2021-26813: Fedoraproject Fedora

High severity, CVSS 7.5. EPSS: 2.3% chance of exploitation in the next 30 days.

markdown2 >=1.0.1.18, fixed in 2.4.0, is affected by a regular expression denial of service vulnerability. If an attacker provides a malicious string, it can make markdown2 processing difficult or delayed for an extended period of time.

Affected products

• Fedoraproject Fedora: version 32 only; version 33 only; version 34 only
• MARKDOWN2 Project MARKDOWN2: from 1.0.1.18, before 2.4.0 (fixed in 2.4.0)

Published 2021-03-03. Last modified 2026-06-17.