Bug 2498691

Summary: CVE-2026-15308 python3.6: Python: CPU Denial of Service in HTML parser via repeated unterminated markup declarations [fedora-all]
Product: [Fedora] Fedora Reporter: Jon Moroney <jmoroney>
Component: python3.6Assignee: Nobody's working on this, feel free to take it <nobody>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: 45CC: cstratak, mhroncok, python-maint, python-packagers-sig, torsava, vstinner
Target Milestone: ---Keywords: Reopened, Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e4e01e88-5029-4403-9e37-e412899c09b1"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-09-07 05:56:45 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2498608    

Description Jon Moroney 2026-07-09 20:10:00 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

The incremental HTML parser (html.parser.HTMLParser) allows for CPU
denial-of-service through repeated unterminated markup declarations when
processing uncontrolled data.

Comment 1 Aoife Moloney 2026-08-17 15:16:44 UTC
This bug appears to have been reported against 'rawhide' during the Fedora Linux 45 development cycle.
Changing version to 45.