CVE-2026-15308
HIGH severity · CVSS 7.5 · Uncontrolled resource consumption
7.5CVSS HIGH
Summary
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)1%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Official patch: https://github.com/python/cpython/commit/07efb08123ba9367a7107325adb9d5626dca1ca9 ↗
Additional information
- NVD record
- https://github.com/python/cpython/commit/07efb08123ba9367a7107325adb9d5626dca1ca9Patch
- https://github.com/python/cpython/commit/7933f4bf7131aa4140750f9404f5de0aa2969cedPatch
- https://github.com/python/cpython/commit/bcf98ddbc40ec9b3ee87da0124a5660b19b7e606Patch
- https://github.com/python/cpython/commit/e9f92ac0b298292e7ff998e52cb8ccacfb27a0bdPatch
- https://github.com/python/cpython/issues/153030Patch
- https://github.com/python/cpython/pull/153031Patch
- https://github.com/python/cpython/commit/785df8f743800661961528970f8598edcd291c14
- https://mail.python.org/archives/list/security-announce@python.org/thread/F6453LWKSHKCTWFLCOURWPLETNUIW2Z5/