GitHub Advisoryadvisory · npm

GHSA-rmmh-p597-ppvv Showdown vulnerable to Regular Expression Denial of Service (ReDoS) in link/anchor parsing

MEDIUM Published 2024-02-26 Modified 2026-04-24 Official page ↗
Aliases
CVE-2024-1899
Ecosystem
npm
Packages
showdown
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weaknesses
CWE-674, CWE-777
Reviewed
2026-04-24

Affected packages

• npm showdown: <= 2.1.0 (no fix yet)

Description

Showdownjs, versions <= 2.1.0, `anchors` subparser used to parse links has a nested regular expression which can lead to denial of service conditions given malicious input.

Related

Alias · CVE (1)

  • CVE-2024-1899 An issue in the anchors subparser of Showdownjs versions <= 2.1.0 could allow a remote attacker to cause denial of service conditions. vulnerability

Weakness · CWE (2)

  • CWE-674 Uncontrolled Recursion weakness
  • CWE-777 Regular Expression without Anchors weakness

References