Security Advisory: Improper Authentication in Multiple TP-Link WiFi Repeaters (CVE-2026-109506)

Vulnerability and Impact Description:

CVE-2026-109506: Improper Authentication in Multiple TP-Link WiFi Repeaters

Multiple TP-Link Wi-Fi range extenders use a custom, reversible XOR-and-dictionary transformation in the HTTP web-management login flow. An unauthenticated attacker on the same local network who can capture the network traffic associated with legitimate administrator login may be able to derive an alternative credential value that produces the same accepted authentication result and use it to authenticate to the device’s web-management interface with administrator privileges. Exploitation requires the management login to use HTTP and the attacker to observe the session key, dictionary, and login value associated with a legitimate administrator login.

Successful exploitation may allow an unauthenticated adjacent attacker to gain administrator access to the affected device and modify exposed configuration settings.

CVSS v4.0 Score: 5.9 / Medium

CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Affected Products/Versions and Fixes:

Recommendations:

We strongly recommend that users with affected devices take the following actions:

1. Update affected devices to the latest firmware version that fixed the vulnerability:

EN: Download Center | TP-Link

US: Download Center | TP-Link

Disclaimer:

This advisory is provided for informational purposes only and is subject to change without notice. The information is provided “as is” without warranties of any kind. TP-Link recommends that customers promptly apply available firmware updates or implement documented workarounds as provided in this advisory. Devices/systems that are not updated or mitigated as described may remain vulnerable, and TP-Link disclaims any responsibility or liability for any damages or losses arising from a failure to implement such updates.