Bug 2511857 (CVE-2026-67870)

Summary: CVE-2026-67870 open62541: open62541: Denial of Service via incomplete validation in AddReferences
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in open62541. A remote attacker can exploit an incomplete validation flaw in the server-side AddReferences implementation. By sending a specially crafted request, an attacker can cause a null pointer dereference, leading to a Denial of Service (DoS) condition. This can make the server unavailable to legitimate users.
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Bug Depends On: 2511891    
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Description OSIDB Bzimport 2026-08-05 23:21:26 UTC 
In open62541 v1.5.5, the server-side AddReferences implementation contains an incomplete validation flaw for non-local ExpandedNodeId targets. A remote attacker can send a crafted AddReferencesRequest with an empty targetServerUri and a non-zero targetNodeId.serverIndex, causing the target node pointer to remain NULL while execution continues.