Bug 2511270 (CVE-2026-67858)

Summary: CVE-2026-67858 open62541: open62541: Denial of Service via buffer overflow in Local Discovery Server
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in open62541. When the Local Discovery Server (LDS) is configured with multicast discovery via the MDNSD backend, an unauthenticated remote attacker can exploit a buffer overflow vulnerability. By sending numerous unique discovery URLs in RegisterServer or RegisterServer2 requests, the attacker can cause the server to crash, leading to a denial of service.
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Bug Depends On: 2511509    
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Description OSIDB Bzimport 2026-08-04 22:02:46 UTC
Buffer Overflow vulnerability exists in open62541 1.5.5 when the Local Discovery Server (LDS) is built with multicast discovery enabled through the MDNSD backend. An unauthenticated remote attacker can send a RegisterServer or RegisterServer2 request containing many unique discoveryUrls. This allows remote attackers to cause a denial of service.