Is CVE-2026-5684 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5684 being exploited in the wild.

How severe is CVE-2026-5684?

High severity, with a CVSS score of 8, published 6 April 2026.

Which products and versions are affected?

Tenda CX12L Router 16.03.53.12.

Is there a fix for CVE-2026-5684?

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-2026-5684 attacked?

It is attacked from the adjacent network.

Am I affected by CVE-2026-5684?

Check whether you run Tenda Cx12l, Tenda CX12L Router or Tenda Cx12l 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.

CVE-2026-5684: Tenda CX12L stack overflow in fromwebExcptypemanFilter

CVE-2026-5684 · Severity: high · CVSS 8 · Published 2026-04-06

A security vulnerability exists in the Tenda CX12L router, a device used to provide wireless internet connectivity. An attacker on the local network can exploit this flaw to crash the router or potentially take full control of the device. This could lead to a complete loss of internet access, monitoring of network traffic, or unauthorized access to other devices connected to the same network.

Technologies: Tenda Cx12l, Tenda CX12L Router, Tenda Cx12l Firmware. Vendors: Tenda.

Quick answers

Is CVE-2026-5684 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5684 being exploited in the wild.
How severe is CVE-2026-5684?: High severity, with a CVSS score of 8, published 6 April 2026.
Which products and versions are affected?: Tenda CX12L Router 16.03.53.12.
Is there a fix for CVE-2026-5684?: 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-2026-5684 attacked?: It is attacked from the adjacent network.
Am I affected by CVE-2026-5684?: Check whether you run Tenda Cx12l, Tenda CX12L Router or Tenda Cx12l 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 stack-based buffer overflow vulnerability exists in the Tenda CX12L router (firmware 16.03.53.12) within the 'fromwebExcptypemanFilter' function of the '/goform/webExcptypemanFilter' endpoint. The root cause is the unsafe use of 'sprintf' when processing the user-controlled 'page' parameter, which is copied into a fixed-size 256-byte buffer without length validation. An attacker with local network access can send a specially crafted POST request with an oversized 'page' argument to overwrite adjacent memory on the stack. Successful exploitation can lead to a Denial of Service (DoS) by crashing the web server or arbitrary code execution by overwriting return addresses. A public PoC is available.

Affected products

Tenda CX12L Router 16.03.53.12

Timeline

2026-03-30: disclosed: Vulnerability details and PoC shared on GitHub.
2026-04-06: advisory: CVE-2026-5684 published.

References

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