TP-Link Omada SDN Software Controller before 5.0.15 does not check if the authentication method specified in a connection request is allowed. An attacker can bypass the captive portal authentication process by using the downgraded "no authentication" method, and access the protected network. For example, the attacker can simply set window.authType=0 in client-side JavaScript.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-44032
• https://github.com/Orange-Cyberdefense/CVE-repository/blob/master/PoCs/POC_CVE-2021-44032_Kevin.md
• https://www.tp-link.com/us/omada-sdn/
• https://www.tp-link.com/us/security