Bug 2544596

Summary: CVE-2026-103679 tnef: Use-after-free and double-free in get_body_files() via multi-value body extraction [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: tnefAssignee: Artur Frenszek-Iwicki <fedora>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: dtimms, fedora
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["d9b862d7-0485-4fc0-b356-e49fecdd99c0"]}
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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: 2544477    

Description Vladimir Vasilev 2026-10-01 11:37:44 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.

A flaw was found in tnef. When a TNEF stream contains more than one MAPI RTF or HTML body value, get_body_files() allocates a single filename buffer and a single MIME-type buffer and assigns the same pointers to every generated output file, instead of a separate copy per file. Each of these files is later freed independently, producing a use-after-free followed by a double-free on the second and subsequent files. The issue was confirmed under AddressSanitizer and crashes the process when extracting a crafted TNEF stream with multiple body values; no code-execution primitive has been demonstrated.