CVE-2025-6069

medium

Description

The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.

References

https://mail.python.org/archives/list/[email protected]/thread/K5PIYLR6EP3WR7ZOKKYQUWEDNQVUXOYM/

https://github.com/python/cpython/pull/135464

https://github.com/python/cpython/issues/135462

https://github.com/python/cpython/commit/fdc9d214c01cb4588f540cfa03726bbf2a33fc15

https://github.com/python/cpython/commit/f3c6f882cddc8dc30320d2e73edf019e201394fc

https://github.com/python/cpython/commit/d851f8e258c7328814943e923a7df81bca15df4b

https://github.com/python/cpython/commit/ab0893fd5c579d9cea30841680e6d35fc478afb5

https://github.com/python/cpython/commit/8d1b3dfa09135affbbf27fb8babcf3c11415df49

https://github.com/python/cpython/commit/6eb6c5dbfb528bd07d77b60fd71fd05d81d45c41

https://github.com/python/cpython/commit/4455cbabf991e202185a25a631af206f60bbc949

Details

Source: Mitre, NVD

Published: 2025-06-17

Updated: 2025-07-07

Risk Information

CVSS v2

Base Score: 5.4

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 4.3

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L