Vulnerability Description
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
CVSS Score
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Python | Python | < 3.10.21 |
Related Weaknesses (CWE)
References
- https://github.com/python/cpython/commit/07efb08123ba9367a7107325adb9d5626dca1caPatch
- https://github.com/python/cpython/commit/1e7956f1a722df9aabc509c30f8fbdc3a2b4fdcPatch
- https://github.com/python/cpython/commit/785df8f743800661961528970f8598edcd291c1Patch
- https://github.com/python/cpython/commit/7933f4bf7131aa4140750f9404f5de0aa2969cePatch
- https://github.com/python/cpython/commit/bcf98ddbc40ec9b3ee87da0124a5660b19b7e60Patch
- https://github.com/python/cpython/commit/c2390b9376e35a701ed3acc597b8fc87546c9b0Patch
- https://github.com/python/cpython/commit/e9f92ac0b298292e7ff998e52cb8ccacfb27a0bPatch
- https://github.com/python/cpython/issues/153030Patch
- https://github.com/python/cpython/pull/153031Issue TrackingPatch
- https://mail.python.org/archives/list/[email protected]/thread/F6453LMailing List
- http://www.openwall.com/lists/oss-security/2026/07/09/4Third Party Advisory
FAQ
What is CVE-2026-15308?
CVE-2026-15308 is a vulnerability with a CVSS score of 7.5 (HIGH). The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
How severe is CVE-2026-15308?
CVE-2026-15308 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-15308?
Check the references section above for vendor advisories and patch information. Affected products include: Python Python.