Bug 2572353

Summary: CVE-2026-127029 freeradius: Stack-based buffer overflow via unbounded EAP-SIM identity length [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: freeradiusAssignee: Antonio Torres <antorres>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: antorres, lemenkov
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["6cf5241b-ee9e-414a-b565-556e3521f8b3"]}
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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: 2572339    

Description Vladimir Vasilev 2026-11-12 12:21:57 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 freeradius's EAP-SIM module. The server copies the client-supplied EAP identity into an internal key-derivation structure without bounding its length against the destination field, and the resulting length is then used unchecked when deriving session keys, copying attacker-controlled data past the end of a fixed-size stack buffer. An unauthenticated client exchanging EAP-SIM messages with a server that has the module enabled can trigger this to crash the RADIUS server process.