{"id":"CVE-2025-6069","title":"The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.","summary":"The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.","severity":"medium","cvss":4.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","cwe":["CWE-1333"],"published":"2025-06-17","updated":"2026-07-30","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-6069","references":[{"url":"https://github.com/python/cpython/commit/4455cbabf991e202185a25a631af206f60bbc949","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/6eb6c5dbfb528bd07d77b60fd71fd05d81d45c41","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/8d1b3dfa09135affbbf27fb8babcf3c11415df49","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/ab0893fd5c579d9cea30841680e6d35fc478afb5","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/d851f8e258c7328814943e923a7df81bca15df4b","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/f3c6f882cddc8dc30320d2e73edf019e201394fc","label":"cna@python.org"},{"url":"https://github.com/python/cpython/commit/fdc9d214c01cb4588f540cfa03726bbf2a33fc15","label":"cna@python.org"},{"url":"https://github.com/python/cpython/issues/135462","label":"cna@python.org"},{"url":"https://github.com/python/cpython/pull/135464","label":"cna@python.org"},{"url":"https://mail.python.org/archives/list/security-announce@python.org/thread/K5PIYLR6EP3WR7ZOKKYQUWEDNQVUXOYM/","label":"cna@python.org"}],"tags":["nvd"],"epss":0.00589,"epssPercentile":0.46857,"ingestedAt":"2026-07-31T06:58:50.948Z","slug":"CVE-2025-6069","body":"## Overview\n\nThe html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":24,"depthScoreParts":{"impact":23.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}