~ / search / GHSA-cr32-g25g-vxjj

GHSA-cr32-g25g-vxjj

showdown metadata title handling allows cross-site scripting

Source: GitHub Advisory Database (reviewed) Moderate CVE-2026-59711

Packages

EcosystemPackageAffectedFixed in
npm showdown <= 2.1.0 no fix listed

Details

As written in the advisory (Markdown source, shown as plain text).

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.

References

External links from the advisory. They lead to third-party sites.