Critical (9.8). EPSS 1.5% chance of exploitation in the next 30 days. Fixed in commonmarker 0.23.4.
CommonMarker versions prior to 0.23.4 are at risk of an integer overflow vulnerability. This vulnerability can result in possibly unauthenticated remote attackers to cause heap memory corruption, potentially leading to an information leak or remote code execution, via parsing tables with marker rows that contain more than UINT16_MAX columns.
Severity
CVSS 3.1
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.5% chance of exploitation in the next 30 days; higher than 73% of CVEs (scores of 2026-10-31)