CVE-2019-25781
markdown: python-markdown: Denial of Service via inefficient inline link parsing
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 29, 2026
Updated · October 31, 2026
Description
A flaw was found in Python-Markdown. An algorithmic complexity vulnerability in inline link parsing allows a remote attacker to cause a Denial of Service (DoS) by exhausting CPU resources. By submitting specially crafted Markdown text containing repeated unmatched brackets, an attacker can force the parser into inefficient scanning loops that consume excessive CPU time and stall worker processes.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-606 · Unchecked Input for Loop Condition