Bug 2560118

Summary: CVE-2026-115352 python-mistune08: mistune: Denial of Service via unmatched brackets in inline link parser [epel-9]
Product: [Fedora] Fedora EPEL Reporter: Ronit Dey <rdey>
Component: python-mistune08Assignee: Orphan Owner <extras-orphan>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: epel9CC: epel-packagers-sig, extras-orphan, neil, python-packagers-sig
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["82d2fe82-d537-4b89-98b5-bf5033c012b8"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2559293    

Description Ronit Dey 2026-10-23 17:43:28 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.

Mistune before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser that allows unauthenticated attackers to exhaust CPU by submitting long runs of unmatched '[' characters. Attackers can send small markdown payloads that trigger O(N^2) parse_link_text and parse_link_label probing, occupying rendering workers for 30+ seconds per 16 KB input.