Is CVE-2026-5685 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5685 being exploited in the wild.

How severe is CVE-2026-5685?

High severity, with a CVSS score of 8.8, published 6 April 2026.

Is there a fix for CVE-2026-5685?

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-2026-5685 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-5685?

Check whether you run Tenda Cx12l 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-2026-5685: Tenda CX12L stack buffer overflow in fromAddressNat

CVE-2026-5685 · Severity: high · CVSS 8.8 · Published 2026-04-06

A security vulnerability has been identified in the Tenda CX12L router, a device used for home and business networking. An attacker can exploit this flaw to cause the device to crash or potentially take full control of the router. This could lead to unauthorized monitoring of network traffic, service outages, or the use of the router as a stepping stone to attack other devices on the internal network.

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

Quick answers

Is CVE-2026-5685 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5685 being exploited in the wild.
How severe is CVE-2026-5685?: High severity, with a CVSS score of 8.8, published 6 April 2026.
Which products and versions are affected?: Tenda Cx12l 16.03.53.12.
Is there a fix for CVE-2026-5685?: 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-2026-5685 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5685?: Check whether you run Tenda Cx12l 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 version 16.03.53.12. The flaw is located in the 'fromAddressNat' function within the '/goform/addressNat' endpoint. The root cause is the unsafe use of 'sprintf' to process the user-controlled 'page' parameter into a fixed-size 256-byte buffer without length validation. A remote attacker can exploit this by sending a specially crafted POST request with an oversized 'page' argument. Successful exploitation can lead to memory corruption, allowing for denial of service (DoS) or arbitrary code execution (ACE) by overwriting the return address on the stack. A public proof-of-concept (PoC) is available.

Affected products

Tenda CX12L 16.03.53.12

Timeline

2026-03-30: disclosed: Vulnerability details and PoC shared on GitHub by researcher.
2026-04-06: advisory: Initial publication of CVE-2026-5685.

References

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