Research · Jun 17, 2025
Out-of-Bounds Read Vulnerability Discovered in Citrix NetScaler ADC and Gateway
A critical out-of-bounds read vulnerability has been identified in Citrix NetScaler ADC and Gateway, potentially exposing sensitive memory content.
What changed
Citrix has announced a significant vulnerability in its NetScaler ADC and Gateway products. This out-of-bounds read issue arises from inadequate input validation, which could allow unauthorized memory access.
- The vulnerability is particularly concerning when the NetScaler is configured as a Gateway, including VPN virtual servers.
- It can also affect setups using ICA Proxy, CVPN, RDP Proxy, or AAA virtual servers.
Who is affected
Various organizations utilizing Citrix NetScaler products may be at risk due to this vulnerability. The following groups are particularly affected:
- Enterprise users relying on Citrix NetScaler ADC for application delivery.
- Organizations using Citrix Gateway for secure remote access.
- IT departments managing VPN configurations with Citrix products.
What to do
It is crucial for affected organizations to assess their configurations and implement necessary security measures. Citrix recommends the following actions:
- Review and update Citrix NetScaler ADC and Gateway to the latest security patches.
- Conduct a thorough security audit to identify any potential exposure.
- Ensure that input validation practices are robust to mitigate similar vulnerabilities.