{"id":"CVE-2026-59710","summary":"showdown - Stored XSS via Unescaped Table Header ID Attribute Injection","details":"showdown contains a stored cross-site scripting vulnerability in the parseHeaders function of src/subParsers/makehtml/tables.js that fails to properly escape table header ID attributes. Attackers can inject arbitrary HTML and script-executing SVG elements through double-quote characters in markdown table headers, achieving stored XSS when untrusted markdown is rendered with the default github flavor configuration.","aliases":["GHSA-22g5-r2x5-97cx"],"modified":"2026-08-07T21:25:59.283165547Z","published":"2026-07-06T21:15:45.900Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59710.json","cna_assigner":"VulnCheck","cwe_ids":["CWE-79"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59710.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59710"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/showdown-stored-xss-via-unescaped-table-header-id-attribute-injection"},{"type":"REPORT","url":"https://github.com/showdownjs/showdown/issues/1046"},{"type":"FIX","url":"https://github.com/showdownjs/showdown/commit/e5cab1e9a5dcea2bb3cbf888863fa7e65ab37edf"},{"type":"PACKAGE","url":"https://github.com/showdownjs/showdown"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/showdownjs/showdown","events":[{"introduced":"0"},{"fixed":"e5cab1e9a5dcea2bb3cbf888863fa7e65ab37edf"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"2.1.0"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["3.0.0-rc2","3.0.0-rc1","1.8.5","1.8.4","1.8.3","1.8.2","1.8.1","1.8.0","1.7.6","1.7.5","1.7.4","1.7.3","1.7.2","1.7.1","1.7.0","1.6.4","1.6.3","1.6.2","1.6.1","1.6.0","1.5.5","1.5.4","1.5.3","1.5.2","1.5.1","1.5.0","1.4.4","1.4.3","1.4.2","1.4.0","1.3.0","1.2.2","1.2.1","1.2.0","1.1.0","1.0.2","1.0.1","1.0.0","0.5.1","1.0.0-alpha.2","1.0.0-alpha1","0.5.0","0.4.0","v0.3.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59710.json"}}],"schema_version":"1.8.0","severity":[{"type":"CVSS_V4","score":"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"}]}