# CVE-2026-36741: U-SPEED AC1200 Router command injection in NTP configuration

Source: https://junglewise.ai/threats/cve-2026-36741-u-speed-ac1200-router-command-injection-in-ntp-configuration  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-13. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-36741 · Severity: high · CVSS 7.2 · Published 2026-05-13

The U-SPEED AC1200 Gigabit Wi-Fi Router is a networking device used to provide internet connectivity. A security flaw in its time synchronization settings allows an authorized administrator to run unauthorized system commands. This could lead to a complete takeover of the device, allowing an attacker to monitor network traffic, steal credentials, or disrupt internet service.

Vendors: [U-SPEED](https://junglewise.ai/threats/vendors/u-speed).

## Quick answers

**Is CVE-2026-36741 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-36741 being exploited in the wild.

**How severe is CVE-2026-36741?** High severity, with a CVSS score of 7.2, published 13 May 2026.

**Which products and versions are affected?** U-SPEED AC1200 Gigabit Wi-Fi Router (T18-21K) V1.0.

**Is there a fix for CVE-2026-36741?** 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-2026-36741 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-36741?** Check whether you run U-SPEED AC1200 Gigabit Wi-Fi Router (T18-21K), U-SPEED T18-21k or U-SPEED T18-21k Firmware 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 command injection vulnerability exists in the /api/system/ntp endpoint of the U-SPEED AC1200 (T18-21K) router firmware V1.0. The application fails to properly sanitize user-supplied input in the 'ntpSrv1' parameter before passing it to a system shell. An authenticated attacker with administrative privileges can use shell metacharacters (e.g., '&') to execute arbitrary operating system commands as root. This can be used to access sensitive files like /etc/passwd or establish persistence. No official patch is currently noted in the advisory, though remediation should involve input validation and avoiding shell execution functions.

## Affected products

- U-SPEED AC1200 Gigabit Wi-Fi Router (T18-21K) V1.0

## Timeline

- 2026-05-13: disclosed
- 2026-05-13: advisory

## References

- [https://github.com/N0tMilk/vulnerability-research](https://github.com/N0tMilk/vulnerability-research)
- [https://github.com/N0tMilk/vulnerability-research/tree/main/IoT/CVE-2026-36741](https://github.com/N0tMilk/vulnerability-research/tree/main/IoT/CVE-2026-36741)

## Related threats

- [U-SPEED AC1200 Router unauthenticated UART interface access](https://junglewise.ai/threats/cve-2026-36738-u-speed-ac1200-router-unauthenticated-uart-interface-access)