CVE-2020-15515 in turn Extension
Summary
by MITRE
The turn extension through 0.3.2 for TYPO3 allows Remote Code Execution.
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Analysis
by VulDB Data Team • 10/29/2020
The vulnerability identified as CVE-2020-15515 affects the turn extension version 0.3.2 within the TYPO3 content management framework, presenting a critical remote code execution flaw that can be exploited by attackers without authentication. This vulnerability specifically targets the extension's handling of user input within its processing logic, creating a pathway for malicious actors to execute arbitrary commands on the affected server. The issue stems from insufficient input validation and sanitization mechanisms within the extension's codebase, allowing crafted payloads to bypass security controls and gain unauthorized access to system resources.
The technical implementation of this vulnerability involves improper handling of parameters passed to the turn extension's backend processing functions. When the extension processes incoming requests containing malicious input, it fails to adequately sanitize or validate the data before incorporating it into system commands or database queries. This weakness creates a direct path for command injection attacks where attacker-controlled code can be executed with the privileges of the web application. The flaw aligns with CWE-77 and CWE-94 categories, representing command injection and code injection vulnerabilities respectively, which are fundamental security weaknesses that enable arbitrary code execution. The attack surface is particularly concerning as it operates at the extension level, meaning that exploitation does not require compromising the core TYPO3 system but can be achieved through the vulnerable third-party component.
The operational impact of this vulnerability is severe and multifaceted, as successful exploitation can lead to complete system compromise, data breaches, and unauthorized access to sensitive information. Attackers can leverage this vulnerability to establish persistent access, install backdoors, exfiltrate databases, or use the compromised server for further attacks against other systems. The remote nature of the exploit means that attackers can target vulnerable systems from anywhere on the internet without requiring physical access or prior authentication. This vulnerability particularly affects organizations running TYPO3 installations with the vulnerable turn extension, potentially exposing them to advanced persistent threats and credential theft. According to ATT&CK framework categorization, this vulnerability maps to T1059.001 (Command and Scripting Interpreter: PowerShell) and T1203 (Exploitation for Client Execution) techniques, highlighting the execution and persistence capabilities that attackers can achieve through this flaw.
Organizations should immediately implement mitigations including updating the turn extension to a patched version that addresses the input validation issues, applying the latest TYPO3 core updates, and implementing network-level restrictions to limit access to extension endpoints. Security measures should include input validation at multiple layers, including web application firewall rules to detect and block suspicious payloads, and comprehensive monitoring of system logs for signs of exploitation attempts. The vulnerability also underscores the importance of maintaining up-to-date third-party components and implementing proper security testing procedures for extensions before deployment. Organizations should conduct thorough vulnerability assessments of their TYPO3 installations to identify all potentially affected extensions and ensure that security patches are applied promptly. Additionally, implementing principle of least privilege access controls and regular security audits can help reduce the attack surface and limit the potential damage from successful exploitation attempts.