{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59928","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-07-07T18:20:06.126Z","datePublished":"2026-07-08T16:23:21.000Z","dateUpdated":"2026-07-08T19:40:43.968Z"},"containers":{"cna":{"title":"Mistune block_parser: quadratic-time parsing on long lists of repeated reference-link definitions","problemTypes":[{"descriptions":[{"cweId":"CWE-407","lang":"en","description":"CWE-407: Inefficient Algorithmic Complexity","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/lepture/mistune/security/advisories/GHSA-ffq3-xpv3-j92q","tags":["x_refsource_CONFIRM"],"url":"https://github.com/lepture/mistune/security/advisories/GHSA-ffq3-xpv3-j92q"},{"name":"https://github.com/lepture/mistune/commit/2b04d7ba341c16ac78fe82d3076bdd5c3de87c69","tags":["x_refsource_MISC"],"url":"https://github.com/lepture/mistune/commit/2b04d7ba341c16ac78fe82d3076bdd5c3de87c69"},{"name":"https://github.com/lepture/mistune/releases/tag/v3.3.0","tags":["x_refsource_MISC"],"url":"https://github.com/lepture/mistune/releases/tag/v3.3.0"}],"affected":[{"vendor":"lepture","product":"mistune","versions":[{"version":"< 3.3.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-07-08T16:23:21.000Z"},"descriptions":[{"lang":"en","value":"Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0."}],"source":{"advisory":"GHSA-ffq3-xpv3-j92q","discovery":"UNKNOWN"}},"adp":[{"references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-ffq3-xpv3-j92q","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-08T17:46:13.539153Z","id":"CVE-2026-59928","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"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":"2026-07-08T19:40:43.968Z"}}]}}