CVE-2026-67858

Description

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.

References

• https://github.com/open62541/open62541/blob/master/doc/building.rst
• https://github.com/open62541/open62541/blob/master/src/server/ua_discovery_mdns.c
• https://github.com/open62541/open62541/blob/master/src/server/ua_services_discovery.c
• https://github.com/open62541/open62541/issues/8094
• https://github.com/open62541/open62541/tree/master/examples/discovery