CVE-2026-67870
open62541 OPC UA server flaw allows remote crash and possible memory corruption.
Is CVE-2026-67870 being exploited?
Not confirmed. CVE-2026-67870 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.57% probability of exploitation in the next 30 days.
How severe is CVE-2026-67870?
CVE-2026-67870 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-67870?
Not known from our data. No patch reference has been recorded for CVE-2026-67870, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-67870 affect?
CVE-2026-67870 affects open62541 v1.5.5, OPC UA servers using open62541, Embedded industrial devices bundling the library. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-67870?
Apply vendor/library patch when available; block AddReferences RPC and monitor OPC UA traffic.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can send crafted AddReferencesRequest causing NULL-pointer use leading to server crash (DoS) and potential memory corruption or RCE.
Immediate action required