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CVE-2026-4769 WAGO CVE debrief

CVE-2026-4769 involves an undocumented diagnostic capability in WAGO System I/O Field series devices, briefly accessible without authentication during boot, allowing full system compromise. This vulnerability has a critical CVSS score of 9.3 and requires immediate attention from organizations using these devices. The diagnostic capability, not formally documented, poses a significant risk as it can be exploited by unauthenticated remote attackers to gain access to internal system processes.

Vendor
WAGO
Product
0765-110x/0100-0000
CVSS
CRITICAL 9.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-13
Original CVE updated
2026-07-13
Advisory published
2026-07-13
Advisory updated
2026-07-13

Who should care

Organizations using WAGO System I/O Field series devices should prioritize patching and monitor for potential exploitation attempts. Security teams and vulnerability management teams should review the official CVE record and NVD entry for detailed information on affected products and mitigation strategies. Operators of these devices must assess their exposure and implement compensating controls if patches are not immediately available.

Technical summary

The WAGO System I/O Field series devices activate an internal diagnostic capability during the initial startup sequence. This functionality is not formally documented and becomes accessible without authentication for a brief period in the early boot phase. During this window, an unauthenticated remote attacker can gain access to the internal system processes, resulting in full system compromise. The vulnerability has a CVSS score of 9.3, indicating critical severity.

Defensive priority

High priority due to critical CVSS score of 9.3 and potential for full system compromise.

Recommended defensive actions

  • Apply vendor patches or updates to disable the undocumented diagnostic capability.
  • Implement network segmentation to limit access to WAGO System I/O Field series devices.
  • Monitor for suspicious activity and potential exploitation attempts.
  • Conduct regular security audits and vulnerability assessments.
  • Review compensating controls for exposed systems while remediation is scheduled and verified.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record was published on 2026-07-13T08:16:21.343Z and has not been modified since then. The NVD entry is currently being reviewed. Evidence is limited to public sources and may not reflect the full scope of affected systems. Defenders should verify potential exposure with WAGO System I/O Field series device deployments and review official advisories for detailed mitigation guidance.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-13T08:16:21.343Z and has not been modified since then.