Race condition in NetScaler ADC and NetScaler Gateway occurs when the appliance is set as a Gateway for SSL VPN, ICA Proxy, CVPN, RDP Proxy, or an AAA virtual server. The condition allows two concurrent session creation processes to interfere, causing the authentication information of one user to be swapped with that of another. This mix‑up can let an attacker observe or interact with a different user's session state, resulting in unintended access to data or functionality. The vulnerability is a classic race condition (CWE‑847) affecting confidentiality and potentially integrity of user sessions.

The flaw impacts Citrix NetScaler ADC and NetScaler Gateway appliances configured for Gateway mode (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or as an AAA virtual server. No specific firmware versions are listed in the advisory, so all current installations matching those configurations are potentially vulnerable.

The CVSS base score of 7.7 indicates a high severity, while the EPSS score of less than 1 % suggests a low probability of widespread exploitation at present. The vulnerability is not present in the CISA KEV catalog. Attacks would require successful manipulation of the appliance’s session handling logic, likely over a network channel used for VPN or proxy traffic. Because no public exploit has been disclosed, the practical risk remains moderate to high for environments exposing unpatched Gateways, but the attack surface is limited to the specific configuration types.