CVE-2020-20595 in OPMS
Summary
by MITRE • 12/23/2021
A cross-site request forgery (CSRF) in OPMS v1.3 and below allows attackers to arbitrarily add a user account via /user/add.
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Analysis
by VulDB Data Team • 12/26/2021
The vulnerability identified as CVE-2020-20595 represents a critical cross-site request forgery flaw within OPMS version 1.3 and earlier releases. This weakness resides in the application's user management functionality, specifically at the /user/add endpoint which lacks proper CSRF protection mechanisms. The vulnerability enables malicious actors to exploit the absence of anti-CSRF tokens or validation controls, allowing unauthorized individuals to programmatically create new user accounts within the system without proper authorization. This represents a fundamental breakdown in the application's security controls and demonstrates poor implementation of web application security principles.
The technical implementation of this vulnerability stems from the application's failure to enforce CSRF protection measures at the user account creation endpoint. Modern web applications must implement anti-CSRF tokens that are generated per session and validated on each state-changing request to prevent unauthorized operations. The absence of such controls means that an attacker can craft malicious requests that, when executed by an authenticated user, will result in unauthorized account creation. This flaw operates under CWE-352 which specifically addresses Cross-Site Request Forgery vulnerabilities and aligns with ATT&CK technique T1078.004 for Valid Accounts and T1566.001 for Phishing. The vulnerability essentially allows attackers to perform privilege escalation through unauthorized account creation, potentially enabling them to gain persistent access to the system.
The operational impact of this vulnerability extends beyond simple account creation, as it provides attackers with a means to establish persistent access to the system. Once an attacker successfully creates a new user account, they can leverage this access to perform additional malicious activities including data exfiltration, system reconnaissance, or further privilege escalation. The vulnerability affects the integrity and availability of the system's user management functionality, potentially leading to unauthorized access to sensitive information and system resources. The flaw also undermines the principle of least privilege and demonstrates a critical failure in the application's access control mechanisms, as the system cannot distinguish between legitimate and malicious requests to the user creation endpoint.
Organizations affected by this vulnerability should implement immediate mitigations including the deployment of anti-CSRF tokens at all state-changing endpoints, particularly the /user/add functionality. The recommended approach involves generating unique tokens for each user session and validating these tokens on every request that modifies system state. Additionally, implementing proper session management controls, enforcing referer header validation, and utilizing the SameSite cookie attributes can provide additional layers of protection. Security teams should conduct comprehensive penetration testing to identify other endpoints that may lack CSRF protection, as this vulnerability likely indicates broader security implementation gaps. The mitigation strategy should also include monitoring for unauthorized account creation attempts and implementing proper logging and alerting mechanisms to detect potential exploitation attempts. Organizations should also consider implementing web application firewalls and access control policies to further restrict access to administrative functions and user management endpoints.