# CVE-2026-82784: Contec CONPROSYS nano Remote I/O Coupler auth bypass in REST API

Source: https://junglewise.ai/threats/cve-2026-82784-contec-conprosys-nano-remote-i-o-coupler-auth-bypass-in-rest-api  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-14. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-82784 · Severity: medium · CVSS 6.5 · Published 2026-09-14

Contec CONPROSYS nano Remote I/O Coupler Unit is an industrial control device used to read and manage electrical I/O signals in factory automation systems. An unauthenticated attacker can call REST API functions to remotely read sensor values or control equipment outputs without any login credentials, potentially disrupting manufacturing operations or stealing sensor data.

Technologies: [Contec CONPROSYS nano Remote I/O Coupler Unit (Server Type) CPSN-MCB271](https://junglewise.ai/threats/technologies/conprosys-nano-remote-i-o-coupler-unit-server-type-cpsn-mcb271). Vendors: [Contec](https://junglewise.ai/threats/vendors/contec).

## Quick answers

**Is CVE-2026-82784 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-82784 being exploited in the wild.

**How severe is CVE-2026-82784?** Medium severity, with a CVSS score of 6.5, published 14 September 2026.

**Which products and versions are affected?** Contec CONPROSYS nano Remote I/O Coupler Unit (Server Type) CPSN-MCB271 prior to 1.82.

**Is there a fix for CVE-2026-82784?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-82784 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-82784?** Check whether you run Contec CONPROSYS nano Remote I/O Coupler Unit (Server Type) CPSN-MCB271 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

This is a missing authentication vulnerability (CWE-306) in the REST API of the CONPROSYS nano Remote I/O Coupler Unit (Server Type). The vulnerability allows an unauthenticated network attacker to invoke API endpoints that retrieve I/O values or control output states without providing credentials. The attack vector is network-based with no authentication required and no user interaction needed. An attacker can exploit this to both read sensitive sensor data and manipulate industrial control outputs remotely. The fix is available in version 1.82 or later for the CPSN-MCB271-* product line.

## Affected products

- Contec CONPROSYS nano Remote I/O Coupler Unit (Server Type) CPSN-MCB271 prior to 1.82

## Timeline

- 2026-09-10: disclosed
- 2026-09-14: advisory

## References

- [https://jvn.jp/en/vu/JVNVU96551518/](https://jvn.jp/en/vu/JVNVU96551518/)
- [https://www.contec.com/api/downloadlogger?download=/-/media/Contec/support/security-info/2026/contec_security_cps_26091000_en.pdf](https://www.contec.com/api/downloadlogger?download=/-/media/Contec/support/security-info/2026/contec_security_cps_26091000_en.pdf)

## Related threats

- [Contec CONPROSYS nano Remote I/O Coupler insufficiently protected credentials](https://junglewise.ai/threats/cve-2026-82786-contec-conprosys-nano-remote-i-o-coupler-insufficiently-protected)
- [Contec CONPROSYS nano Remote I/O Coupler Unit stack-based buffer overflow](https://junglewise.ai/threats/cve-2026-82785-contec-conprosys-nano-remote-i-o-coupler-unit-stack-based-buffer)