CVE-2020-22761 in FlatPress
Summary
by MITRE • 07/30/2021
Cross Site Request Forgery (CSRF) vulnerability in FlatPress 1.1 via the DeleteFile function in flat/admin.php.
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Analysis
by VulDB Data Team • 08/06/2021
The CVE-2020-22761 vulnerability represents a critical Cross Site Request Forgery flaw discovered in FlatPress version 1.1, specifically within the DeleteFile function of the flat/admin.php administrative interface. This vulnerability exposes the content management system to unauthorized file deletion operations that can be triggered through maliciously crafted web requests. The flaw exists due to insufficient validation of request origins and lack of proper anti-CSRF token implementation within the administrative functions, allowing attackers to manipulate the system's file deletion capabilities without proper authorization. The vulnerability is particularly concerning as it directly targets the administrative interface where critical system operations are performed, potentially enabling complete compromise of the FlatPress installation.
The technical implementation of this CSRF vulnerability stems from the absence of proper request validation mechanisms within the DeleteFile function. When an administrator performs file deletion operations through the administrative panel, the system fails to verify that the request originates from a legitimate administrative session. This lack of origin verification creates an exploitable condition where an attacker can craft a malicious request that, when executed by an authenticated administrator, results in unintended file deletion. The vulnerability is classified under CWE-352, which specifically addresses Cross-Site Request Forgery weaknesses, and aligns with ATT&CK technique T1190 for Exploit Public-Facing Application, as it targets the web interface of the application. The flaw demonstrates poor input validation practices and inadequate session management within the administrative components of the CMS.
The operational impact of CVE-2020-22761 extends beyond simple file deletion, as it can lead to complete system compromise and data loss. Attackers exploiting this vulnerability can remove critical system files, including core application files, configuration files, or user data, potentially rendering the FlatPress installation unusable. The administrative access required for exploitation means that successful attacks can result in persistent compromise of the web server hosting the CMS, as attackers may delete security-related files or replace them with malicious alternatives. This vulnerability also enables attackers to disrupt service availability by deleting essential components, making the system inaccessible to legitimate users and administrators. The impact is particularly severe in environments where FlatPress serves as a primary content management solution for websites or blogs.
Mitigation strategies for CVE-2020-22761 should focus on implementing robust anti-CSRF protection mechanisms within the FlatPress administrative interface. The most effective approach involves incorporating anti-CSRF tokens into all administrative operations, ensuring that each request contains a unique, unpredictable token that validates the legitimacy of the session. Organizations should also implement proper request origin validation, ensuring that administrative requests originate from the expected domain and are not being submitted through unauthorized third-party domains. Additionally, implementing proper session management with secure session identifiers and automatic session timeout mechanisms can help reduce the window of opportunity for exploitation. System administrators should immediately upgrade to patched versions of FlatPress where available, as the vulnerability is remediated through proper implementation of CSRF protection measures. Network-level defenses such as web application firewalls can provide additional protection, though they should not be considered a substitute for proper application-level fixes. Regular security audits of administrative interfaces and input validation mechanisms should be conducted to prevent similar vulnerabilities from emerging in other components of the system.