Is CVE-2026-15701 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-15701 being exploited in the wild.

How severe is CVE-2026-15701?

Critical severity, with a CVSS score of 9.8, published 14 July 2026.

Which products and versions are affected?

TOTOLINK Nr1800x 9.1.0u.6279_B20210910.

Is there a fix for CVE-2026-15701?

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-2026-15701 attacked?

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

Am I affected by CVE-2026-15701?

Check whether you run TOTOLINK Nr1800x 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-2026-15701: Totolink NR1800X stack overflow in Form_Logout

CVE-2026-15701 · Severity: critical · CVSS 9.8 · Published 2026-07-14

A critical security vulnerability has been identified in the Totolink NR1800X wireless router, a device used to provide internet connectivity in homes and small offices. An attacker can exploit this flaw to remotely crash the device or potentially take full control of it without needing a password. This could lead to a complete loss of internet service or unauthorized access to the network traffic passing through the router.

Technologies: TOTOLINK Nr1800x. Vendors: TOTOLINK.

Quick answers

Is CVE-2026-15701 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-15701 being exploited in the wild.
How severe is CVE-2026-15701?: Critical severity, with a CVSS score of 9.8, published 14 July 2026.
Which products and versions are affected?: TOTOLINK Nr1800x 9.1.0u.6279_B20210910.
Is there a fix for CVE-2026-15701?: 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-2026-15701 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-15701?: Check whether you run TOTOLINK Nr1800x 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 (CWE-121) exists in the Form_Logout function within the vendor-customized lighttpd binary (/usr/sbin/lighttpd) of the Totolink NR1800X firmware version 9.1.0u.6279_B20210910. The vulnerability is located in the /formLogout.htm endpoint, where the userloginAuth() function fails to perform authentication or session validation before processing the request. An attacker can trigger the overflow by sending a GET request to /formLogout.htm with a Host header exceeding 245 bytes, which is then processed by an unsafe strcpy() operation. This allows for remote code execution (RCE) or denial of service (DoS) without any user interaction or valid credentials.

Affected products

Totolink NR1800X 9.1.0u.6279_B20210910

Timeline

2026-06-11: disclosed: Initial discovery and PoC published on GitHub
2026-07-14: advisory: CVE published to NVD dataset

References

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