VulnerabilityDeferred
CVE-2025-6069
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.
MEDIUM 4.3EPSS 0.55%
Does this matter?
Lower severity and a low EPSS score (0.55%). Track it; it rarely justifies an emergency change on its own.
Description
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.55% probability · 44th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-1333
- Source
- cna@python.org
References
- https://github.com/python/cpython/commit/4455cbabf991e202185a25a631af206f60bbc949
- https://github.com/python/cpython/commit/6eb6c5dbfb528bd07d77b60fd71fd05d81d45c41
- https://github.com/python/cpython/commit/8d1b3dfa09135affbbf27fb8babcf3c11415df49
- https://github.com/python/cpython/commit/ab0893fd5c579d9cea30841680e6d35fc478afb5
- https://github.com/python/cpython/commit/d851f8e258c7328814943e923a7df81bca15df4b
- https://github.com/python/cpython/commit/f3c6f882cddc8dc30320d2e73edf019e201394fc
- https://github.com/python/cpython/commit/fdc9d214c01cb4588f540cfa03726bbf2a33fc15
- https://github.com/python/cpython/issues/135462
- https://github.com/python/cpython/pull/135464
- https://mail.python.org/archives/list/security-announce@python.org/thread/K5PIYLR6EP3WR7ZOKKYQUWEDNQVUXOYM/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.