CVE-2019-17370 in OTCMS
Summary
by MITRE
OTCMS v3.85 allows arbitrary PHP Code Execution because admin/sysCheckFile_deal.php blocks "into outfile" in a SELECT statement, but does not block the "into/**/outfile" manipulation. Therefore, the attacker can create a .php file.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 01/07/2024
The vulnerability identified as CVE-2019-17370 affects OTCMS version 3.85 and represents a critical security flaw that enables arbitrary PHP code execution through a sophisticated bypass technique. This vulnerability stems from an insufficient input validation mechanism within the admin/sysCheckFile_deal.php component of the content management system. The flaw demonstrates a classic example of incomplete input sanitization where the developers attempted to block malicious SQL operations by filtering out the "into outfile" directive but failed to account for obfuscation techniques that could circumvent the protection.
The technical implementation of this vulnerability exploits a specific pattern of SQL injection where attackers can manipulate SQL statements through comment syntax to bypass the security restrictions. The system blocks the direct execution of "into outfile" commands but does not account for variations such as "into/**/outfile" where the forward slashes serve as comment delimiters in MySQL syntax. This obfuscation technique allows attackers to execute the malicious SQL statement while maintaining the appearance of legitimate database operations. The bypass occurs because the filtering mechanism operates on literal string matching rather than parsing the actual SQL syntax, creating a gap in the security controls.
The operational impact of this vulnerability is severe as it provides attackers with persistent code execution capabilities within the web application's environment. Once exploited, an attacker can create arbitrary PHP files on the server, effectively granting them the ability to execute arbitrary code with the privileges of the web application. This access can be leveraged to establish persistent backdoors, exfiltrate sensitive data, or compromise the entire server infrastructure. The vulnerability is particularly dangerous because it requires minimal privileges to exploit and can be automated, making it attractive to both automated attacks and determined threat actors.
Organizations affected by this vulnerability should implement immediate mitigations including updating to the latest version of OTCMS where the issue has been addressed through proper input validation and SQL statement parsing. The fix should involve comprehensive filtering that accounts for comment-based obfuscation techniques and proper SQL statement analysis rather than simple string matching. Security measures should also include implementing web application firewalls with SQL injection detection capabilities and regular security audits of input validation mechanisms. From a compliance perspective, this vulnerability aligns with CWE-94 which describes improper control of generation of code and represents a significant deviation from secure coding practices. The attack pattern demonstrates characteristics consistent with ATT&CK technique T1059.007 for command and scripting interpreter, specifically PHP, indicating that this vulnerability could be exploited as part of broader attack chains targeting web application infrastructure.