In short
- CVE-2026-59711 is a MEDIUM (CVSS 6.1) vulnerability affecting showdown.
- Chance of exploitation in the next 30 days (EPSS): 0.23%, higher than 13.9% of all vulnerabilities.
- No patched version is listed yet: follow the vendor's advisory in References.
| Package | Affected versions | Patched versions |
|---|
| showdown npm | ≤ 2.1.0
| No fix yet |
Description
showdown contains a cross-site scripting vulnerability in metadata title handling that allows attackers to inject arbitrary HTML and JavaScript. When completeHTMLDocument option is enabled, unescaped less-than and greater-than characters in markdown frontmatter metadata are inserted directly into HTML title tags, enabling attackers to break out of the title context and execute malicious scripts in the rendered page.
NVD description
showdown contains a cross-site scripting vulnerability in metadata title handling that allows attackers to inject arbitrary HTML and JavaScript. When completeHTMLDocument option is enabled, unescaped less-than and greater-than characters in markdown frontmatter metadata are inserted directly into HTML title tags, enabling attackers to break out of the title context and execute malicious scripts in the rendered page.
Running one of these products? Scan your site to see whether it exposes a vulnerable version.
Scan my site free