Consultant warns on Citrix deployment vulnerabilities
Ongoing testing has revealed flaws in Citrix implementations, but no action has been taken six months later.


An IT security consultancy has today said that its testing of Citrix implementations has uncovered widespread vulnerability issues the application delivery vendor has failed to address.
The issue, first revealed to Citrix by Global Secure Systems (GSS) six months ago, has affected 100 per cent of deployments tested by the UK consultancy, leaving them vulnerable to arbitrary code execution.
Although the issues are not an issue with Citrix itself or its applications, GSS warned that the vulnerabilities it had uncovered were "potentially devastating" result of poor implementation of Citrix.
Robin Hollington, GSS director of consulting, told IT PRO that too many IT organisations install Citrix without comprehensive knowledge of the design and management of the Citrix environment and careful consideration of how to mitigate risk.
Having discovered the issues and then noticed more discussion of them in hacker communities, GSS decided to publicise details from the findings of its Citrix Environment Security Assessment (CESA), developed in response to possible attack methods it identified.
The ongoing GSS assessments have found more than 80 per cent of deployments exposed commercially sensitive data and many breached Data Protection Act requirements.
It further found standard security procedures were not applied to most Citrix deployments, in environments ranging from Citrix for Windows NT 4.0 to the latest Citrix nFuse deployments on Windows 2003 Server.
Get the ITPro daily newsletter
Sign up today and you will receive a free copy of our Future Focus 2025 report - the leading guidance on AI, cybersecurity and other IT challenges as per 700+ senior executives
Hollington added that, with very little specialist knowledge, a hacker could gain access to a poorly configured Citrix system in as little as 30 seconds. But, given the potential for misuse, GSS would not publish exact details of the CESA test methods undertaken.
He did give an example of the scale of the threat: "In a financial services company, we found a spreadsheet containing the domain admin passwords for each and every server. Our assessments prove that this information can be readily accessed with very little knowledge and easily leaked out of the business."
Hollington said Citrix do provide regularly updated hardening guides' for configuring their products. But he suggested IT organisations either don't use them or become lax in adhering to them after completing a few deployments.
And applying additional mitigation measures merely addressed the symptoms, not the causes and can often target expenditure in the wrong areas, he added.
Testing is therefore essential to identify the real issues and select the appropriate controls, said Hollington.
Citrix had not responded to a request for information at the time of writing.
A 25-year veteran enterprise technology expert, Miya Knights applies her deep understanding of technology gained through her journalism career to both her role as a consultant and as director at Retail Technology Magazine, which she helped shape over the past 17 years. Miya was educated at Oxford University, earning a master’s degree in English.
Her role as a journalist has seen her write for many of the leading technology publishers in the UK such as ITPro, TechWeekEurope, CIO UK, Computer Weekly, and also a number of national newspapers including The Times, Independent, and Financial Times.
-
How the UK MoJ achieved secure networks for prisons and offices with Palo Alto Networks
Case study Adopting zero trust is a necessity when your own users are trying to launch cyber attacks
By Rory Bathgate
-
Putting small language models under the microscope
ITPro Podcast The benefits of small language models are undeniable – but they're no silver bullet
By Rory Bathgate
-
Citrix Bleed an “early Christmas present” for hackers as flaw claims latest victim
News Xfinity is the latest firm to fall victim to the Citrix Bleed vulnerability
By George Fitzmaurice
-
Citrix Bleed remains out of control with thousands of appliances still vulnerable
News Thousands of organizations at risk of Citrix Bleed have still not patched, analysis suggests
By Ross Kelly
-
What is Citrix Bleed and should you be worried?
News A critical buffer over-read can expose sensitive information in affected devices
By Rory Bathgate
-
Patch-resistant autonomous exploits of Citrix NetScaler hardware hit thousands in Europe
News More than 1,800 Citrix NetScaler devices still contained backdoors at the time of publication
By Rory Bathgate
-
Citrix discloses critical NetScaler Gateway vulnerability
News Users of affected products have been urged to implement patches immediately to mitigate risk
By Ross Kelly
-
Citrix patches XenMobile vulnerability
News Positive Technologies spots serious flaw in Citrix XenMobile
By Nicole Kobie
-
Hackers are taking advantage of Citrix vulnerabilities
News Hackers discovered targeting corporate networks impacted by Citrix vulnerabilities
By Sarah Brennan
-
Citrix Synergy 2019: One year on GDPR is shaping the role of privacy in brand survival
In-depth Despite big fines levied, Citrix’s privacy chief says we still don’t have a sense of what enforcement will look like
By Keumars Afifi-Sabet