Software Engineering Institute

Citrix NetScaler and Access Gateway Enterprise Edition contain a vulnerability which could allow a remote attacker to gain unauthorized access to network resources.

For additional information please see Citrix Advisory.

A remote attacker could gain unauthorized access to internal network resources.

Upgrade

Citrix Advisory states:

A new version of the NetScaler appliance firmware has been released to address this vulnerability. Citrix strongly recommends that affected customers upgrade their appliances to version 9.3.62.x or later as soon as possible. Customers using NetScaler Access Gateway Enterprise Edition in the Common Criteria evaluated configuration should upgrade to 9.3.53.6. These new firmware versions can be downloaded from the Citrix website at the following location: https://www.citrix.com/downloads/netscaler-adc/firmware.html

Customers using NetScaler appliance firmware versions up to and including 10.0.74.4 in a double hop deployment should apply the following configuration change from the NSCLI:

>add ns acl allowedHost ALLOW -srcIP <MIP/SNIP address of AGEE in the first DMZ> -destIP <ICA proxy VIP> -priority 10 #permit traffic only from the AGEE appliance in the first DMZ

>enable ns acl allowedHost

>add ns acl denyAll DENY -srcIP 0.0.0.0 - 255.255.255.255 -destIP <ICA proxy VIP> -priority 20 #block everything else

>enable ns acl denyAll
>apply ns acls