Security Advisory: Multiple Vulnerabilities in Omada Gateways (CVE-2026-9033, CVE-2026-19586, CVE-2026-19683)

Description of Vulnerabilities and Impact:

CVE-2026-9033: Unauthenticated Captive Portal Session Termination and Forced Logout

An unauthenticated attacker with network access to the captive portal service of an affected device can terminate active captive portal sessions, including forcing logout of specific users or clearing all active sessions. Affected users must re-authenticate to regain access.

Successful exploitation may allow termination of individual or all active captive portal sessions, causing temporary service disruption and requiring users to re-authenticate.

CVSS v4.0 Score: 6.0 / Medium

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

CVE-2026-19586: Pre-Authentication OS Command Injection in Omada Gateways on OpenVPN Server

A pre-authentication OS command injection vulnerability has been identified in Omada gateways configured to operate as an OpenVPN Server due to insufficient validation of client-supplied data during OpenVPN connection establishment. An unauthenticated remote attacker may provide specially crafted input influencing backend command execution logic before authentication completes. Exploitation requires the OpenVPN Server feature to be enabled, VPN service must be reachable by the attacker, and the attacker must be able to initiate an OpenVPN connection attempt.

Successful exploitation may allow arbitrary command execution, potentially leading to full compromise of the affected device.

CVSS v4.0 Score: 9.3 / Critical

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

CVE-2026-19683: Unencrypted Credential Transmission in Omada Gateway Dynamic DNS Authentication

A vulnerability exists in the Dynamic DNS (DDNS) functionality of TP-Link Omada Gateways. During communication with a third-party DDNS service, authentication credentials are transmitted over an unencrypted channel. An attacker who can observe or manipulate traffic between an affected device and the DDNS service may obtain sensitive authentication information or interfere with DDNS update operations. Exploitation requires DDNS to be configured, communication with an external DDNS service, and attacker visibility or control of the relevant network path.

Successful exploitation may result in disclosure of DDNS account credentials, unauthorized access to DDNS management functionality, or modification of DNS records associated with the affected deployment.

CVSS v4.0 Score: 6.3 / Medium

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/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

Workarounds:

CVE-2026-19586: If immediate firmware upgrade is not possible, users should disable the OpenVPN Server feature until the fixed firmware can be applied. If OpenVPN Server must remain enabled, restrict access to the OpenVPN service to trusted networks or trusted source IP addresses only, and ensure the service is not exposed to the public Internet unless required.

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.