Citrix confirmed a critical vulnerability in Citrix Gateway and Citrix ADC products. Here's what you need to know.
On December 13, 2022, Citrix released an advisory detailing a critical security flaw in Citrix Gateway and Citrix Application Delivery Controller (ADC). Citrix Gateway is commonly used as a remote access solution and Citrix ADC is a networking appliance for web applications. The security flaw (CVE-2022-27518) allows a remote, unauthenticated attacker to perform arbitrary code execution. Citrix reports that this vulnerability is being actively exploited by attackers. A security patch has been released and should be applied as soon as possible.
The vulnerability affects the following products and versions:
- Citrix ADC and Citrix Gateway 13.0 before 13.0-58.32
- Citrix ADC and Citrix Gateway 12.1 before 12.1-65.25
- Citrix ADC 12.1-FIPS before 12.1-55.291
- Citrix ADC 12.1-NDcPP before 12.1-55.291
Citrix ADC and Citrix Gateway version 13.1 is unaffected.
For exploitation, the Citrix ADC or Citrix Gateway must be configured as a SAML SP or a SAML IdP. See instructions under “Next Steps” to determine if your appliance is configured as a SAML SP or a SAML IdP. If you are unable to determine, we recommend upgrading to the latest version out of caution.
Without a security patch, an unauthenticated remote attacker may be able to gain access to an affected Gateway or ADC appliance and execute arbitrary code. From there the attacker could move around the network and conduct further exploitation. Corvus has observed similar vulnerabilities lead to ransomware attacks.
Note: This only applies to customer-managed Citrix ADC and Citrix Gateway appliances. Customers using Citrix-managed cloud services or Citrix-managed Adaptive Authentication do not need to take any action.
Next steps for Citrix customers:
- Upgrade to a non-vulnerable version of ADC or Gateway as soon as possible:
- Citrix ADC and Citrix Gateway 13.0-58.32 and later releases
- Citrix ADC and Citrix Gateway 12.1-65.25 and later releases of 12.1
- Citrix ADC 12.1-FIPS 12.1-55.291 and later releases of 12.1-FIPS
- Citrix ADC 12.1-NDcPP 12.1-55.291 and later releases of 12.1-NDcPP
- Customers can determine if their Citrix ADC or Citrix Gateway is configured as a SAML SP or a SAML IdP by inspecting the ns.conf file for the following commands:
Appliance is configured as a SAML SP
add authentication samlAction
Appliance is configured as a SAML IdP
add authentication samlIdPProfileIf either of the commands are present in the ns.conf file and if the version is an affected version, then it is critical that the appliance be updated.
- If you require technical assistance with this issue, please contact Citrix Technical Support.