{"id":"GHSA-cr32-g25g-vxjj","revision":"c54c8860cd9b4db8baed0870eb95bbbb","records":[{"revision":"c54c8860cd9b4db8baed0870eb95bbbb","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-cr32-g25g-vxjj","aliases":["CVE-2026-59711"],"title":"showdown metadata title handling allows cross-site scripting","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.","state":0,"publishedAt":"2026-07-06T21:30:43+00:00","modifiedAt":"2026-09-10T03:51:11.5235337+00:00","affected":[{"ecosystem":"npm","name":"showdown","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"last_affected","version":"2.1.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":null,"severity":null},{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://nvd.nist.gov/vuln/detail/CVE-2026-59711","https://github.com/showdownjs/showdown/issues/1047","https://github.com/showdownjs/showdown/commit/184a3e4e97f90e075c4512f2c4c06dcf655e91b7","https://github.com/showdownjs/showdown","https://www.vulncheck.com/advisories/showdown-cross-site-scripting-via-unescaped-metadata-title-in-completehtmldocument"],"sourceUrl":"https://github.com/advisories/GHSA-cr32-g25g-vxjj","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-cr32-g25g-vxjj","identifiers":["GHSA-cr32-g25g-vxjj","CVE-2026-59711"]},"retained":false,"historicalAffected":[]}],"coverage":[]}