Gateway
CVE-2021-22920
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Access control enforcement
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAI
A vulnerability has been discovered in Citrix ADC (formerly known as NetScaler ADC) and Citrix Gateway (formerly known as NetScaler Gateway), and Citrix SD-WAN WANOP Edition models 4000-WO, 4100-WO,. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified under CWE-284. A vulnerability has been discovered in Citrix ADC (formerly known as NetScaler ADC) and Citrix Gateway (formerly known as NetScaler Gateway), and Citrix SD-WAN WANOP Edition models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. These vulnerabilities, if exploited, could lead to a phishing attack through a SAML authentication hijack to steal a valid user session. Affected products include: Citrix Application Delivery Management, Citrix Gateway.
Know when Gateway gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
A vulnerability has been discovered in Citrix ADC (formerly known as NetScaler ADC) and Citrix Gateway (formerly known as NetScaler Gateway), and Citrix SD-WAN WANOP Edition models 4000-WO, 4100-WO, 5000-WO, and 5100-WO. These vulnerabilities, if exploited, could lead to a phishing attack through a SAML authentication hijack to steal a valid user session.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
Citrix NetScaler ADC and NetScaler Gateway deployments running builds prior to 14.1-73.37 or 13.1-64.23 (including the c
Unauthenticated command execution in Citrix NetScaler ADC (before 14.1-73.37, before 13.1-64.23, and the corresponding F
A remote, unauthenticated attacker can cause a denial-of-service condition on NetScaler ADC and NetScaler Gateway applia
An insufficient input validation vulnerability exists in Citrix NetScaler ADC and NetScaler Gateway when configured as a
The Gzip file parser in AVG Anti-Virus 10.0.0.1190, Bitdefender 7.2, Command Antivirus 5.2.11.5, Emsisoft Anti-Malware 5
The TAR file parser in AhnLab V3 Internet Security 2011.01.18.00, Avira AntiVir 7.11.1.163, Antiy Labs AVL SDK 2.0.3.7,
The CAB file parser in Dr.Web 5.0.2.03300, Trend Micro HouseCall 9.120.0.1004, Kaspersky Anti-Virus 7.0.0.125, Sophos An
HTTP request smuggling (CWE-444) in Citrix NetScaler ADC and NetScaler Gateway allows unauthenticated, remote attackers
Predictable value generation in Citrix NetScaler ADC and Gateway (CWE-342) lets unauthenticated remote attackers predict
The TAR file parser in Avira AntiVir 7.11.1.163, Antiy Labs AVL SDK 2.0.3.7, Quick Heal (aka Cat QuickHeal) 11.00, Emsis
Remote unauthenticated attackers can trigger a memory overflow in Citrix NetScaler ADC and Gateway, leading to unpredict
A memory overflow in Citrix NetScaler ADC and NetScaler Gateway can be triggered by unauthenticated remote attackers (CV
GitHub PoC
Exploit-DB