Bug 2522061

Summary: CVE-2026-77658 dia: dia: stack buffer overflow in Bus object via unvalidated handle count in project files [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Ganesh <gnaik>
Component: diaAssignee: Robert Scheck <redhat-bugzilla>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: huzaifas, redhat-bugzilla
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["ecf3a683-7a5a-4a82-8f04-d19a54943567"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On:    
Bug Blocks: 2520890    

Description Ganesh 2026-08-24 16:35:50 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 Dia's Network Bus object loader. When opening a crafted Dia project (.dia) file, the bus_handles attribute supplies num_handles without validation. Later, when a bus handle is moved, bus_handle_moved() allocates two arrays on the stack using g_alloca() sized by num_handles, which can exhaust the thread stack and cause memory corruption, application crash, or potentially arbitrary code execution. The same g_alloca pattern exists in objects/Misc/tree.c.