{"cve":"CVE-2025-69534","nvd":{"published":"2026-03-05T15:16:11.243","modified":"2026-09-07T13:17:57.517","status":"Modified","description":"Python-Markdown version 3.8 contain a vulnerability where malformed HTML-like sequences can cause html.parser.HTMLParser to raise an unhandled AssertionError during Markdown parsing. Because Python-Markdown does not catch this exception, any application that processes attacker-controlled Markdown may crash. This enables remote, unauthenticated Denial of Service in web applications, documentation systems, CI/CD pipelines, and any service that renders untrusted Markdown. The issue was acknowledged by the vendor and fixed in version 3.8.1. This issue causes a remote Denial of Service in any application parsing untrusted Markdown, and can lead to Information Disclosure through uncaught exceptions.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400","CWE-617"],"references":["https://github.com/Python-Markdown/markdown","https://github.com/Python-Markdown/markdown/actions/runs/15736122892","https://github.com/Python-Markdown/markdown/issues/1534","http://www.openwall.com/lists/oss-security/2026/03/06/4","https://access.redhat.com/errata/RHSA-2026:10184"],"products":["python-markdown:markdown"],"source":"nvd","synced_at":"2026-10-19T22:25:53.701907451+00:00"},"epss":{"cve":"CVE-2025-69534","score":0.00663,"percentile":0.51729,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-5wmx-573v-2qwq","url":"https://osv.dev/vulnerability/GHSA-5wmx-573v-2qwq","summary":"Python-Markdown has an Uncaught Exception","modified":"2026-09-10T03:50:37.537940778Z","packages":[{"ecosystem":"PyPI","name":"markdown","purl":"pkg:pypi/markdown","ranges":["<3.8.1"],"fixed":["3.8.1"]}]},{"id":"PYSEC-2026-89","url":"https://osv.dev/vulnerability/PYSEC-2026-89","summary":"","modified":"2026-06-10T17:02:03.742572395Z","packages":[{"ecosystem":"PyPI","name":"markdown","purl":"pkg:pypi/markdown","ranges":["<=3.8"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}