Nginx Controller
CVE-2020-5901
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.6 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. |
| Exploit ScenarioDerived | A remote attacker could inject malicious scripts into web pages viewed by other users by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
In NGINX Controller 3.3.0-3.4.0, undisclosed API endpoints may allow for a reflected Cross Site Scripting (XSS) attack. Rated critical severity (CVSS 9.6), 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. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Affects your stack
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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 as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. In NGINX Controller 3.3.0-3.4.0, undisclosed API endpoints may allow for a reflected Cross Site Scripting (XSS) attack. If the victim user is logged in as admin this could result in a complete compromise of the system. Affected products include: F5 Nginx Controller.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
In NGINX Controller 3.3.0-3.4.0, undisclosed API endpoints may allow for a reflected Cross Site Scripting (XSS) attack. If the victim user is logged in as admin this could result in a complete compromise of the system.
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
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
Affected Products (CPE)NVD
More in Nginx Controller
View allIn versions 3.0.0-3.9.0, 2.0.0-2.9.0, and 1.0.1, the NGINX Controller Agent does not use absolute paths when calling sys
In versions 3.0.0-3.4.0, 2.0.0-2.9.0, and 1.0.1, there is insufficient cross-site request forgery (CSRF) protections for
In NGINX Controller versions prior to 3.2.0, an unauthenticated attacker with network access to the Controller API can c
On versions 3.0.0-3.3.0, the NGINX Controller webserver does not invalidate the server-side session token after users lo
In versions prior to 3.3.0, the NGINX Controller Agent installer script 'install.sh' uses HTTP instead of HTTPS to check
The NGINX Controller 2.0.0 thru 2.9.0 and 3.x before 3.15.0 Administrator password may be exposed in the systemd.txt fil
In NGINX Controller 3.0.0-3.4.0, recovery code required to change a user's password is transmitted and stored in the dat
On NGINX Controller versions 3.1.0-3.3.0, AVRD uses world-readable and world-writable permissions on its socket, which a
In versions 3.0.0-3.5.0, 2.0.0-2.9.0, and 1.0.1, the Neural Autonomic Transport System (NATS) messaging services in use
Intra-cluster communication does not use TLS. Rated high severity (CVSS 7.4), this vulnerability is remotely exploitable
In versions of NGINX Controller prior to 3.2.0, communication between NGINX Controller and NGINX Plus instances skip TLS
In versions 3.0.0-3.5.0, 2.0.0-2.9.0, and 1.0.1, the NGINX Controller installer starts the download of Kubernetes packag
GitHub PoC
Exploit-DB