Unchecked Input for Loop Condition Affecting markdown-it package, versions >=15.0.0 <15.0.2<14.3.2
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-JS-MARKDOWNIT-21277722
- published20 Oct 2026
- disclosed19 Oct 2026
- creditGSGFs7
Introduced: 19 Oct 2026
NewCVE-2026-111759 (opens in a new tab)How to fix?
Upgrade markdown-it to version 15.0.2, 14.3.2 or higher.
Overview
markdown-it is a modern pluggable markdown parser.
Affected versions of this package are vulnerable to Unchecked Input for Loop Condition via the process_inlines function in src/rules_core/smartquotes.ts when the typographer option is enabled. The smartquotes rule performs a linear scan of the opener stack for every closing quote token, resulting in quadratic time complexity when quote types do not match. An attacker can supply input with a large number of unmatched quote characters to cause a crash through excessive CPU consumption.
Note: This is only exploitable when the typographer: true option is explicitly set, as the default configuration (typographer: false) does not invoke the smartquotes rule.