CVE-2026-19790: Tenda G0 stack buffer overflow in port mirror handler

CVE-2026-19790 · Severity: high · CVSS 8.8 · Published 2026-08-14

Tenda G0 routers contain a buffer overflow vulnerability in the web management interface's port mirroring configuration function. An attacker can remotely send a specially crafted request with an oversized portMirrorMirroredPorts parameter to crash the device or execute arbitrary code, compromising the router's availability and security.

Technologies: Tenda G0. Vendors: Tenda.

Quick answers

Is CVE-2026-19790 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-19790 being exploited in the wild.
How severe is CVE-2026-19790?
High severity, with a CVSS score of 8.8, published 14 August 2026.
Which products and versions are affected?
Tenda G0 up to 20260625.
Is there a fix for CVE-2026-19790?
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-2026-19790 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-19790?
Check whether you run Tenda G0 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 stack-based buffer overflow exists in the formSetPortMirror function within the httpd web management interface (/goform/module endpoint). The vulnerability occurs because the portMirrorMirroredPorts parameter is read from user input and passed directly to sprintf() without length validation, writing into a fixed 256-byte stack buffer. An attacker can exploit this remotely by sending an HTTP request with a crafted portMirrorMirroredPorts value exceeding the buffer size. Successful exploitation can lead to memory corruption, denial of service, or arbitrary code execution. A patch is available and the exploit is publicly disclosed.

Affected products

  • Tenda G0 up to 20260625

Timeline

  • 2026-08-14: disclosed: Published on NVD
  • 2026-08-14: other: Exploit publicly available on GitHub

References

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