Is CVE-2026-5991 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5991 being exploited in the wild.

How severe is CVE-2026-5991?

High severity, with a CVSS score of 8.8, published 10 April 2026.

Is there a fix for CVE-2026-5991?

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-2026-5991 attacked?

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

Am I affected by CVE-2026-5991?

Check whether you run Tenda F451 or Tenda F451 Firmware. 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-2026-5991: Tenda F451 stack overflow in formWrlExtraSet

CVE-2026-5991 · Severity: high · CVSS 8.8 · Published 2026-04-10

A vulnerability exists in the Tenda F451 wireless router, a device used to provide internet connectivity for homes and small offices. An attacker can exploit this flaw to cause a system crash or potentially take full control of the router. This could lead to unauthorized access to network traffic, service outages, or the use of the device as a foothold for further attacks on the internal network.

Technologies: Tenda F451, Tenda F451 Firmware. Vendors: Tenda.

Quick answers

Is CVE-2026-5991 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5991 being exploited in the wild.
How severe is CVE-2026-5991?: High severity, with a CVSS score of 8.8, published 10 April 2026.
Which products and versions are affected?: Tenda F451 1.0.0.7.
Is there a fix for CVE-2026-5991?: 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-2026-5991 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5991?: Check whether you run Tenda F451 or Tenda F451 Firmware. 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 F451 router running firmware version 1.0.0.7. The flaw is located within the 'formWrlExtraSet' function in the '/goform/WrlExtraSet' component. The vulnerability is triggered by improper validation of the 'GO' argument, which allows an attacker to overwrite the stack. While the attack can be launched remotely, it requires low-level authentication (PR:L). Successful exploitation can lead to complete compromise of the device (Confidentiality, Integrity, and Availability impact). A public exploit is reportedly available.

Affected products

Tenda F451 1.0.0.7

Timeline

2026-04-10: disclosed: Initial publication date

References

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