Is CVE-2026-5566 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-5566 being exploited in the wild.

How severe is CVE-2026-5566?

High severity, with a CVSS score of 8.8, published 5 April 2026.

Which products and versions are affected?

UTT HiPER 1250GW up to 3.2.7-210907-180535.

Is there a fix for CVE-2026-5566?

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-2026-5566 attacked?

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

Am I affected by CVE-2026-5566?

Check whether you run UTT HiPER 1250GW 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-2026-5566: UTT HiPER 1250GW buffer overflow in formNatStaticMap

CVE-2026-5566 · Severity: high · CVSS 8.8 · Published 2026-04-05

A security vulnerability exists in the UTT HiPER 1250GW enterprise router, which is used to manage network traffic and connectivity. An attacker can exploit this flaw to cause the device to crash or reboot, potentially leading to a complete network outage. In some cases, this could also allow an attacker to gain unauthorized control over the device or access sensitive data passing through the network.

Technologies: UTT HiPER 1250GW. Vendors: UTT.

Quick answers

Is CVE-2026-5566 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-5566 being exploited in the wild.
How severe is CVE-2026-5566?: High severity, with a CVSS score of 8.8, published 5 April 2026.
Which products and versions are affected?: UTT HiPER 1250GW up to 3.2.7-210907-180535.
Is there a fix for CVE-2026-5566?: 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-2026-5566 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-5566?: Check whether you run UTT HiPER 1250GW 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 UTT HiPER 1250GW router firmware up to version 3.2.7-210907-180535. The flaw is located within the /goform/formNatStaticMap interface, specifically involving the strcpy function. When the 'Action' parameter is not set to 'add', the application fails to validate the length of the 'NatBind' (internally 'NatBinds') parameter before copying it into a fixed-size buffer. An attacker with low-privileged network access can send a specially crafted POST request to trigger the overflow. This results in a denial of service (device crash/reboot) and potentially remote code execution. A public exploit (PoC) is available.

Affected products

UTT HiPER 1250GW up to 3.2.7-210907-180535

Timeline

2026-03-19: disclosed: Initial discovery and PoC shared on GitHub
2026-04-05: advisory: CVE published and VulDB entry created

References

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