GHSA-r7fv-28h4-cvq7: markdown-it (CVE-2026-111759)

Package	Ecosystem	Affected	Fixed in
markdown-it	npm	>=15.0.0, <15.0.2 \|\| <14.3.2	15.0.2, 14.3.2

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Versions of the markdown-it npm package before 14.3.2, and from 15.0.0 before 15.0.2, are affected when the typographer option is enabled. Specially crafted Markdown input can make the smartquotes rule take quadratic processing time, which an attacker can use to cause denial of service in applications that process untrusted input. The default configuration with typographer disabled is not affected. Upgrade to 14.3.2 or 15.0.2; until then, the source suggests disabling typographer or disabling the smartquotes rule.

Written 31 Oct 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
7.5	High	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0059, the 48th percentile, on 9 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 13:33 UTC First seen by agentprime
31 Oct 2026, 13:33 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.