CVE-2024-1899: Showdown vulnerable to Regular Expression Denial of Service (ReDoS) in link/anchor parsing

February 26, 2024 (updated April 24, 2026)

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.

References

github.com/advisories/GHSA-rmmh-p597-ppvv
github.com/showdownjs/showdown
nvd.nist.gov/vuln/detail/CVE-2024-1899
www.tenable.com/security/research/tra-2024-05

Code Behaviors & Features

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