CVE-2022-27510: Critical Citrix ADC and Gateway Authentication Bypass Vulnerability

CVE-2022-27510: Critical Citrix ADC and Gateway Authentication Bypass Vulnerability

Citrix publishes an advisory to address multiple flaws in its ADC and Gateway products, including a critical vulnerability.


On November 8, Citrix published CTX463706, a security bulletin detailing three vulnerabilities impacting Citrix’s Application Delivery Controller (ADC) and Gateway products:

Citrix ADC and Gateway Authentication Bypass Vulnerability
Citrix ADC and Gateway Insufficient Verification of Data Authenticity Vulnerability
Citrix ADC and Gateway Protection Mechanism Failure Vulnerability


CVE-2022-27510 is an authentication bypass vulnerability in Citrix ADC and Gateway. It was assigned a CVSSv3 score of 9.8 and is the only flaw in this bulletin to be labeled as Critical. In its bulletin, Citrix notes that this vulnerability affects appliances that have enabled secure socket layer virtual private network (SSL VPN) functionality or are being used as an Independent Computing Architecture Proxy with authentication. Authentication bypass vulnerabilities like this one could be exploited by an attacker as an initial access vector into a network.

CVE-2022-27513 is an insufficient verification of data authenticity vulnerability in Citrix ADC and Gateway. In its description, Citrix says this vulnerability could allow for remote desktop takeover via phishing. This vulnerability can only be exploited if the appliances are operating as a VPN (Gateway) and have remote desktop protocol proxy functionality enabled.

CVE-2022-27516 is a protection mechanism failure vulnerability in Citrix ADC and Gateway. The mechanism that is failing here is the brute force protection for user logins. This vulnerability can only be exploited if the appliances are operating as a VPN (Gateway) OR when operating as an authentication, authorization, and auditing virtual server and if the “Max Login Attempts” brute force setting is in use.

Historical exploitation leads to urgency in patching CVE-2022-27510

From a historical exploitation perspective, Citrix ADC and Gateway’s have been routinely targeted by a number of threat actors over the last few years through the exploitation of CVE-2019-19781, a critical path traversal vulnerability that was first disclosed in December 2019 and subsequently exploited beginning in January 2020 after exploit scripts for the flaw became publicly available.

CVE-2019-19781 has been leveraged by state-sponsored threat actors with ties to China and Iran, as part of ransomware attacks against various entities including the healthcare sector, and was recently included as part of an updated list of the top vulnerabilities exploited by the People’s Republic of China state-sponsored actors from early October.

Proof of concept

At the time this blog post was published, there were no public proof-of-concept exploits for any of the vulnerabilities disclosed in Citrix’s security bulletin, including CVE-2022-27510.


Citrix have published fixes for several versions of its ADC and Gateway products:

Affected Version
Fixed Version
ADC and Gateway 13.1
ADC and Gateway 13.0
ADC and Gateway 12.1
ADC 12.1-NDcPP

Citrix notes that its versions of ADC and Gateway before 12.1 are end of life and no longer supported. Therefore, customers using prior versions should upgrade to a supported version to address these flaws.

Identifying affected systems

A list of Tenable plugins to identify these vulnerabilities will appear here as they’re released. This link uses a search filter to ensure that all matching plugin coverage will appear as it is released.

Get more information

CTX463706: Citrix Security Bulletins for CVE-2022-27510, CVE-2022-27513, CVE-2022-27516

Join Tenable’s Security Response Team on the Tenable Community.

Learn more about Tenable, the first Cyber Exposure platform for holistic management of your modern attack surface.

Get a free 30-day trial of Vulnerability Management.


​Cyber Exposure Alerts Read More 

More To Explore

We can help improve your Business

Ensure your Organization Assets are well  protected in front of the Cyber Attacks

Delivery Workflow

Register for Free and get your test done withn 24 to 48 hours

See Workflow

Sample Report

Here is a sample report of a Security Testing Engagement

See Sample Report PDF

Work Request

Order your security test and Get Your Report

Get Your Test Report
Generated by Feedzy

1. Client Onboarding

Access to all of Cyber Legion's services is provided through the Web Secure Client Portal. To create a Free account, you can sign up through the portal, or contact the Cyber Legion team and they will set up an account for you.

2. NDA , Agreements & Digital Signature

The integration of Digital Signature in our Web Client Portal allows us to legally sign all necessary documents and agreements, enabling us to carry out security assessments on targeted systems.

3. Submit Work Request

Our pricing structure is adaptable to meet the needs of all clients. By filling out the Work Request Form, you can select from pre-existing services or request a personalized proposal.

The Cyber Legion team will acknowledge your order, set up a project in your account, and proceed with the testing and delivery.

4. Security Testing & Report

We meet agreed upon SLAs and follow security testing framework checklists. Based on our commitment, our team of engineers will utilize all of our tools, automation, and testing capabilities to achieve the objectives.

Within the agreed upon timeframe, you will receive a report on the security test that was conducted, including the results, recommendations, and references for addressing any identified issues.

5. Retesting & Validation of Remediation

We not only identify potential threats, risks, and vulnerabilities, but also provide detailed recommendations for resolution. To ensure complete remediation, we offer complimentary retesting and a range of ongoing security testing options for continued vulnerability detection and verification.