{"id":"CVE-2026-59930","state":"PUBLISHED","title":"Mistune toc / TableOfContents directive: heading IDs use predictable `toc_N` numbering with no slugification, allowing collision with attacker-controlled `id=\"toc_N\"` content","description":"Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the toc plugin and TableOfContents directive generate heading IDs as predictable toc_N values without slugifying the heading text, allowing attacker-controlled id=\"toc_N\" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0.","publishedAt":"2026-07-08T16:13:21.999Z","updatedAt":"2026-07-09T13:54:33.627Z","severity":{"score":4.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["lepture mistune"],"affected":[{"vendor":"lepture","product":"mistune","versions":[{"version":"< 3.3.0","status":"affected"}]}],"references":["https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9","https://github.com/lepture/mistune/commit/c4093c4742ed0d10d9332fb8edb455869b7b581b","https://github.com/lepture/mistune/releases/tag/v3.3.0"],"weaknesses":["CWE-345","CWE-1284"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/59xxx/CVE-2026-59930.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59930","state":"PUBLISHED","datePublished":"2026-07-08T16:13:21.999Z","dateUpdated":"2026-07-09T13:54:33.627Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-07T18:20:06.126Z"},"containers":{"cna":{"title":"Mistune toc / TableOfContents directive: heading IDs use predictable `toc_N` numbering with no slugification, allowing collision with attacker-controlled `id=\"toc_N\"` content","descriptions":[{"lang":"en","value":"Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the toc plugin and TableOfContents directive generate heading IDs as predictable toc_N values without slugifying the heading text, allowing attacker-controlled id=\"toc_N\" content to collide with generated anchors and redirect same-page navigation, CSS selectors, or JavaScript handlers. This issue is fixed in version 3.3.0."}],"affected":[{"vendor":"lepture","product":"mistune","versions":[{"version":"< 3.3.0","status":"affected"}]}],"references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9","name":"https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/lepture/mistune/commit/c4093c4742ed0d10d9332fb8edb455869b7b581b","name":"https://github.com/lepture/mistune/commit/c4093c4742ed0d10d9332fb8edb455869b7b581b","tags":["x_refsource_MISC"]},{"url":"https://github.com/lepture/mistune/releases/tag/v3.3.0","name":"https://github.com/lepture/mistune/releases/tag/v3.3.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-345","lang":"en","description":"CWE-345: Insufficient Verification of Data Authenticity","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1284","lang":"en","description":"CWE-1284: Improper Validation of Specified Quantity in Input","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-08T16:13:21.999Z"},"source":{"advisory":"GHSA-2hm2-hc3v-44h9","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-2hm2-hc3v-44h9","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-09T13:53:53.247241Z","id":"CVE-2026-59930","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-09T13:54:33.627Z"}}]}}}