{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-44898","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-05-07T21:50:33.546Z","datePublished":"2026-05-26T20:41:53.805Z","dateUpdated":"2026-05-27T17:57:38.643Z"},"containers":{"cna":{"title":"Mistune TOC Anchor Injection XSS","problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.1,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/lepture/mistune/security/advisories/GHSA-6269-cqxg-mhhv","tags":["x_refsource_CONFIRM"],"url":"https://github.com/lepture/mistune/security/advisories/GHSA-6269-cqxg-mhhv"},{"name":"https://github.com/lepture/mistune/releases/tag/v3.2.1","tags":["x_refsource_MISC"],"url":"https://github.com/lepture/mistune/releases/tag/v3.2.1"}],"affected":[{"vendor":"lepture","product":"mistune","versions":[{"version":"< 3.2.1","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-05-26T20:41:53.805Z"},"descriptions":[{"lang":"en","value":"Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a <ul> table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href=\"#<id>\") and the text value (used as the visible link label) are inserted into <a> tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href=\"#...\" attribute context, injecting arbitrary HTML tags including <script> blocks directly into the rendered TOC. This vulnerability is fixed in 3.2.1."}],"source":{"advisory":"GHSA-6269-cqxg-mhhv","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-6269-cqxg-mhhv","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-27T17:57:34.250055Z","id":"CVE-2026-44898","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-27T17:57:38.643Z"}}]}}