CVE-2025-6069
MEDIUM4.3EPSS 0.86%HTMLParser quadratic complexity when processing malformed inputs
Published: 6/17/2025Modified: 5/16/2026
Description
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.
Affected packages (9)
- Bitnami/libpythonfrom 0, < 3.9.24, >= 3.10.0, < 3.10.19, >= 3.11.0, < 3.11.14, >= 3.12.0, < 3.12.12, >= 3.13.0, < 3.13.6
- Bitnami/pythonfrom 0, < 3.9.24, >= 3.10.0, < 3.10.19, >= 3.11.0, < 3.11.14, >= 3.12.0, < 3.12.12, >= 3.13.0, < 3.13.6
- Bitnami/python-minfrom 0, < 3.9.24, >= 3.10.0, < 3.10.19, >= 3.11.0, < 3.11.14, >= 3.12.0, < 3.12.12, >= 3.13.0, < 3.13.6
- Debian/jythonfrom 0
- Debian/pypy3from 0, < 7.3.5+dfsg-2+deb11u5
- Debian/python2.7from 0
- Debian/python3.11from 0, < 3.11.2-6+deb12u7
- Debian/python3.13from 0, < 3.13.5-2+deb13u1
- Debian/python3.9from 0, < 3.9.2-1+deb11u4
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
References (12)
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2025-6069
- WEBhttps://github.com/python/cpython/commit/4455cbabf991e202185a25a631af206f60bbc949
- WEBhttps://github.com/python/cpython/commit/6eb6c5dbfb528bd07d77b60fd71fd05d81d45c41
- WEBhttps://github.com/python/cpython/commit/8d1b3dfa09135affbbf27fb8babcf3c11415df49
- WEBhttps://github.com/python/cpython/commit/ab0893fd5c579d9cea30841680e6d35fc478afb5
- WEBhttps://github.com/python/cpython/commit/d851f8e258c7328814943e923a7df81bca15df4b
- WEBhttps://github.com/python/cpython/commit/f3c6f882cddc8dc30320d2e73edf019e201394fc
- WEBhttps://github.com/python/cpython/commit/fdc9d214c01cb4588f540cfa03726bbf2a33fc15
- WEBhttps://github.com/python/cpython/issues/135462
- WEBhttps://github.com/python/cpython/pull/135464
- WEBhttps://mail.python.org/archives/list/[email protected]/thread/K5PIYLR6EP3WR7ZOKKYQUWEDNQVUXOYM/
- WEBhttps://nvd.nist.gov/vuln/detail/CVE-2025-6069