Bug 2511847 (CVE-2026-67863)

Summary: CVE-2026-67863 open62541: open62541: Denial of Service via use-after-free vulnerability
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in open62541. A server-side use-after-free vulnerability exists in the local MonitoredItem callback path. This occurs when the system attempts to use a notification object after it has been deallocated. A remote attacker can exploit this vulnerability to cause a denial of service (DoS), making the affected system unavailable.
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Bug Depends On: 2511919    
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Description OSIDB Bzimport 2026-08-05 22:41:22 UTC
In open62541 1.5.5, a server-side use-after-free exists in the local MonitoredItem callback path. The issue occurs when UA_Subscription_localPublish continues to use the current UA_Notification after a callback invokes UA_Server_deleteMonitoredItem for the current local MonitoredItem. This allows a remote attacker to cause a denial of service.