Is CVE-2025-52221 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2025-52221 being exploited in the wild.

How severe is CVE-2025-52221?

Critical severity, with a CVSS score of 9.8, published 8 April 2026.

Is there a fix for CVE-2025-52221?

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-2025-52221 attacked?

It is attacked over the network, in device firmware.

Am I affected by CVE-2025-52221?

Check whether you run Tenda AC6 or Tenda Ac6 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-2025-52221: Tenda AC6 buffer overflow in formSetCfm

CVE-2025-52221 · Severity: critical · CVSS 9.8 · Published 2026-04-08

The Tenda AC6 router is vulnerable to a critical security flaw in its web management interface. An attacker can exploit this to crash the device or potentially take full control of the router remotely. This could lead to the interception of internet traffic, unauthorized access to the local network, or a complete loss of internet connectivity for the home or office.

Technologies: Tenda AC6, Tenda Ac6 Firmware. Vendors: Tenda.

Quick answers

Is CVE-2025-52221 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2025-52221 being exploited in the wild.
How severe is CVE-2025-52221?: Critical severity, with a CVSS score of 9.8, published 8 April 2026.
Which products and versions are affected?: Tenda AC6 15.03.05.16_multi.
Is there a fix for CVE-2025-52221?: 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-2025-52221 attacked?: It is attacked over the network, in device firmware.
Am I affected by CVE-2025-52221?: Check whether you run Tenda AC6 or Tenda Ac6 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 exists in the 'httpd' executable of the Tenda AC6 router, specifically within the 'formSetCfm' function (associated with the /SetCfm URI path). The vulnerability is triggered by insufficient length validation of the 'funcname', 'funcpara1', and 'funcpara2' parameters received via HTTP requests. A remote, unauthenticated attacker can exploit this by sending a specially crafted request to the device. Successful exploitation can lead to arbitrary code execution (RCE) or a denial-of-service (DoS) condition. The issue is confirmed in firmware version 15.03.05.16_multi.

Affected products

Tenda AC6 15.03.05.16_multi

Timeline

2026-04-08: disclosed
2026-04-08: advisory

References

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