# CVE-2026-82790: Contec PC-HELPER Wireless I/O cross-site scripting

Source: https://junglewise.ai/threats/cve-2026-82790-contec-pc-helper-wireless-i-o-cross-site-scripting  
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-2026-82790 · Severity: medium · CVSS 5.4 · Published 2026-09-14

Contec PC-HELPER Wireless I/O is a remote I/O control device commonly used in industrial and embedded systems. A cross-site scripting (XSS) vulnerability allows an attacker to inject malicious scripts that execute in the context of a logged-in administrator's browser, potentially enabling unauthorized device configuration changes or data theft from the management interface.

Vendors: [Contec](https://junglewise.ai/threats/vendors/contec).

## Quick answers

**Is CVE-2026-82790 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-82790 being exploited in the wild.

**How severe is CVE-2026-82790?** Medium severity, with a CVSS score of 5.4, published 14 September 2026.

**Which products and versions are affected?** Contec PC-HELPER Wireless I/O DIO-0404RY-LWF prior to 1.01.00; Contec PC-HELPER Wireless I/O DIO-0404RY-LWF-US prior to 1.01.00.

**Is there a fix for CVE-2026-82790?** 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-2026-82790 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-82790?** Check whether you run Contec PC-HELPER Wireless I/O DIO-0404RY-LWF or Contec PC-HELPER Wireless I/O DIO-0404RY-LWF-US 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 vulnerability is a reflected cross-site scripting (XSS) flaw (CWE-79) in the web management interface of Contec PC-HELPER Wireless I/O devices. An attacker can craft a malicious URL or web page containing unsanitized input that, when visited by a logged-in user, executes arbitrary JavaScript in the user's browser with access to the management session. The vulnerability requires user interaction (clicking a link or visiting a page) and the victim must be authenticated to the device interface. Successful exploitation allows an attacker to perform arbitrary actions on the device, modify configurations, or steal sensitive data. The vendor has released firmware version 1.01.00 or later to remediate this issue.

## Affected products

- Contec PC-HELPER Wireless I/O DIO-0404RY-LWF prior to 1.01.00
- Contec PC-HELPER Wireless I/O DIO-0404RY-LWF-US prior to 1.01.00

## Timeline

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

## References

- [https://jvn.jp/en/vu/JVNVU90314828/](https://jvn.jp/en/vu/JVNVU90314828/)
- [https://www.contec.com/api/downloadlogger?download=/-/media/Contec/support/security-info/2026/contec_security_ph_26091000_en.pdf](https://www.contec.com/api/downloadlogger?download=/-/media/Contec/support/security-info/2026/contec_security_ph_26091000_en.pdf)

## Related threats

- [Contec PC-HELPER and CONPROSYS cross-site request forgery](https://junglewise.ai/threats/cve-2026-82764-contec-pc-helper-and-conprosys-cross-site-request-forgery)