Vulnerabilities have been uncovered in two Citrix platforms that, if exploited, could give an attacker direct access to a company’s local network, potentially affecting thousands of organizations.
The flaws were found in NetScaler Application Delivery Controller and NetScaler Gateway by Positive Technologies researcher Mikhail Klyuchnikov, who believes about 80,000 companies in 158 countries are at risk. This flaw affects all supported versions of the product and all supported platforms, including Citrix ADC and Citrix Gateway 13.0, Citrix ADC and NetScaler Gateway 12.1, Citrix ADC and NetScaler Gateway 12.0, Citrix ADC and NetScaler Gateway 11.1, and also Citrix NetScaler ADC and NetScaler Gateway 10.5.
Citrix released a set of mitigations after being notified of the issue.
The vulnerability, CVE-2019-19781, has not received a severity level from Citrix, but Positive Technologies believes it should receive a CVSS base score of 10. This issue at hand allows any unauthorized attacker to not only access published applications, but also attack other resources of the company's internal network from the Citrix server.
“Considering the high risk brought by the discovered vulnerability, and how widespread Citrix software is in the business community, we recommend information security professionals take immediate steps to mitigate the threat,” said Dmitry Serebryannikov, director of the security audit department at Positive Technologies.