# CVE-2026-4769: WAGO System I/O Field undocumented diagnostic exposure in boot phase

Source: https://junglewise.ai/threats/cve-2026-4769-wago-system-i-o-field-undocumented-diagnostic-exposure-in-boot  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-13. Updated: 2026-07-13  
License: CC BY 4.0 with a link back

CVE-2026-4769 · Severity: critical · CVSS 9.8 · Published 2026-07-13

WAGO System I/O Field devices, which are used in industrial automation to connect sensors and actuators to control systems, contain an undocumented diagnostic feature that activates during startup. An attacker with network access could exploit this brief window during the boot process to bypass security controls and take full control of the device. This could lead to unauthorized changes in industrial processes, data theft, or complete service disruption.

Vendors: [Wago](https://junglewise.ai/threats/vendors/wago).

## Quick answers

**Is CVE-2026-4769 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-4769 being exploited in the wild.

**How severe is CVE-2026-4769?** Critical severity, with a CVSS score of 9.8, published 13 July 2026.

**Which products and versions are affected?** Wago 0765-110x/0100-0000 1.0.0.0 to < 1.2.1.100; Wago 0765-120x/0100-0000 1.0.0.0 to < 1.2.7.100; Wago 0765-150x/0100-0000 1.0.0.0 to < 1.2.7.103; Wago 0765-2101/0100-0000 1.0.0.0 to < 1.2.1.102; and 4 more.

**Is there a fix for CVE-2026-4769?** A patch was published on 2026-07-13: Fixed firmware versions released for all affected models Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-4769 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2026-4769?** Check whether you run Wago 0765-110x/0100-0000, Wago 0765-120x/0100-0000, Wago 0765-150x/0100-0000 or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is classified as Hidden Functionality (CWE-912) within the firmware of WAGO System I/O Field devices. During the early boot phase, the device exposes an undocumented diagnostic interface that does not require authentication. If an attacker has network reachability to the device during this specific startup window, they can interact with internal system processes before standard security mechanisms are initialized. This allows for an unauthenticated remote attacker to achieve full system compromise, including unauthorized configuration changes and execution of arbitrary commands. WAGO has released firmware updates to address this exposure across the affected product lines.

## Affected products

- WAGO 0765-110x/0100-0000 1.0.0.0 to < 1.2.1.100
- WAGO 0765-120x/0100-0000 1.0.0.0 to < 1.2.7.100
- WAGO 0765-150x/0100-0000 1.0.0.0 to < 1.2.7.103
- WAGO 0765-2101/0100-0000 1.0.0.0 to < 1.2.1.102
- WAGO 0765-2102/0100-0000 1.0.0.0 to < 1.2.5.101
- WAGO 0765-410x/0100-0000 1.0.0.0 to < 1.2.1.100
- WAGO 0765-420x/0100-0000 1.0.0.0 to < 1.2.7.100
- WAGO 0765-450x/0100-0000 1.0.0.0 to < 1.2.7.103

## Timeline

- 2026-07-13: advisory: Initial advisory published by CERT VDE and WAGO
- 2026-07-13: patched: Fixed firmware versions released for all affected models

## References

- [https://www.certvde.com/en/advisories/VDE-2026-031/](https://www.certvde.com/en/advisories/VDE-2026-031/)