CVE-2026-48988

NameCVE-2026-48988
Descriptionmarkdown-it is a Markdown parser. Versions 14.1.1 and below contain a denial-of-service vulnerability when typographer: true is enabled, due to quadratic (O(n^2)) processing in the smartquotes rule. The issue stems from repeatedly modifying strings with replaceAt(), which performs O(n) slicing and concatenation per quote character. This can cause excessive CPU consumption when parsing quote-heavy, user-supplied markdown and may let attackers degrade or disrupt service availability. Although typographer is disabled by default, many production apps enable it for smart typography, making the issue relevant. This issue has been fixed in version 14.2.0.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs1140349

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
node-markdown-it (PTS)bullseye10.0.0+dfsg-2+deb11u1vulnerable
bookworm, trixie22.2.3+dfsg+~12.2.3-2vulnerable
forky, sid22.2.3+dfsg+~12.2.3-4vulnerable

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
node-markdown-itsource(unstable)(unfixed)1140349

Notes

https://github.com/markdown-it/markdown-it/security/advisories/GHSA-6v5v-wf23-fmfq
https://github.com/markdown-it/markdown-it/commit/9ce2087562c45d1e5ddd9f76b990f4b3fbe040e5 (14.2.0)

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