{"cve":{"cve_id":"CVE-2026-44897","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00228,"epss_percentile":0.13358,"epss_as_of":"2026-06-23","description":"Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, HTMLRenderer.heading() builds the opening <hN> tag by string-concatenating the id attribute value directly into the HTML — with no call to escape(), safe_entity(), or any other sanitisation function. A double-quote character \" in the id value terminates the attribute, allowing an attacker to inject arbitrary additional attributes (event handlers, src=, href=, etc.) into the heading element. This vulnerability is fixed in 3.2.1.","published_at":"2026-05-26T20:40:42.290000Z","last_modified_at":null,"cvss_v3_score":6.1,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-79"],"nvd_references":["https://github.com/lepture/mistune/security/advisories/GHSA-v87v-83h2-53w7","https://github.com/lepture/mistune/releases/tag/v3.2.1"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:30:30.271094Z"},"effective_severity":"MEDIUM","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"L","value_label":"Low"},{"metric":"I","name":"Integrity","value":"L","value_label":"Low"},{"metric":"A","name":"Availability","value":"N","value_label":"None"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"lepture","vendor_name":"lepture","product_slug":"mistune","product_name":"mistune","version_start":"< 3.2.1","version_start_inclusive":true,"version_end":"< 3.2.1","version_end_inclusive":true,"cpe23_uri":"cve5:lepture:mistune:< 3.2.1:< 3.2.1"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-v87v-83h2-53w7","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/lepture/mistune/releases/tag/v3.2.1","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-05-26T20:40:42.290000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:54:34.804808Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:34.804808Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:54:34.804808Z","label":"CVSS score revised","source":"cvelistv5"}]}