# CVE-2026-27870: Teldat Regesta Smart HD-PLC cross-site scripting in Hostname field

Source: https://junglewise.ai/threats/cve-2026-27870-teldat-regesta-smart-hd-plc-cross-site-scripting-in-hostname  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-17. Updated: 2026-06-20  
License: CC BY 4.0 with a link back

CVE-2026-27870 · Severity: info · CVSS 4.8 · Published 2026-06-17

A vulnerability exists in the Teldat Regesta Smart HD-PLC, an industrial router used for power-line communications. An attacker with administrative access can inject malicious scripts into the device's configuration file. If a legitimate user views the affected management page, the script could execute, potentially allowing the attacker to perform unauthorized actions or steal session information.

Technologies: [Teldat Regesta Smart HD-PLC - TLDPH16D2](https://junglewise.ai/threats/technologies/regesta-smart-hd-plc-tldph16d2). Vendors: [Teldat](https://junglewise.ai/threats/vendors/teldat).

## Quick answers

**Is CVE-2026-27870 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-27870 being exploited in the wild.

**How severe is CVE-2026-27870?** Informational severity, with a CVSS score of 4.8, published 17 June 2026.

**Which products and versions are affected?** Teldat Regesta Smart HD-PLC - TLDPH16D2 11.02.05.10.02.

**Is there a fix for CVE-2026-27870?** A patch was published on 2026-06-17: Fixed in version 11.02.06.00.02 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-27870 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-2026-27870?** Check whether you run Teldat Regesta Smart HD-PLC - TLDPH16D2 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

A stored cross-site scripting (XSS) vulnerability exists in the Teldat Regesta Smart HD-PLC (TLDPH16D2) firmware version 11.02.05.10.02. The vulnerability is located in the 'Hostname' field of the device configuration file. An authenticated attacker with high privileges (PR:H) can inject a malicious JavaScript payload into this field. When the configuration is processed, the payload is executed in the context of the user's browser at the path /upgrade/query.php?cmd=p+3%3Bversion. This allows for arbitrary code execution in the client-side session. The issue is resolved in firmware version 11.02.06.00.02.

## Affected products

- Teldat Regesta Smart HD-PLC - TLDPH16D2 11.02.05.10.02

## Timeline

- 2026-06-17: disclosed
- 2026-06-17: advisory
- 2026-06-17: patched: Fixed in version 11.02.06.00.02

## References

- [https://support.teldat.com/images/content/docs/Teldat_dm1087_regesta_smart_nessum_series_installation(1).pdf](https://support.teldat.com/images/content/docs/Teldat_dm1087_regesta_smart_nessum_series_installation(1).pdf)
- [https://support.teldat.com/portal/supportcontent?page=cgs-customer-global-support&none=true&language=en-US](https://support.teldat.com/portal/supportcontent?page=cgs-customer-global-support&none=true&language=en-US)
- [https://www.hackrtu.com/blog/CNA-CVE-2026-27870/](https://www.hackrtu.com/blog/CNA-CVE-2026-27870/)
- [https://www.hackrtu.com/blog/CNA-HRTU-0002/](https://www.hackrtu.com/blog/CNA-HRTU-0002/)
- [https://www.teldat.com/es/](https://www.teldat.com/es/)

## Related threats

- [Teldat Regesta Smart HD-PLC XSS in upgrade interface](https://junglewise.ai/threats/cve-2026-27867-an-attacker-with-access-via-network-to-the-regesta-smart-hd-plc)
- [Teldat Regesta Smart HD-PLC information disclosure in query.php](https://junglewise.ai/threats/cve-2026-27868-teldat-regesta-smart-hd-plc-information-disclosure-in-query-php)