CVE-2017-9101 in PlaySMS
Summary
by MITRE
import.php (aka the Phonebook import feature) in PlaySMS 1.4 allows remote code execution via vectors involving the User-Agent HTTP header and PHP code in the name of a file.
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Analysis
by VulDB Data Team • 08/03/2025
The vulnerability identified as CVE-2017-9101 resides within the Phonebook import functionality of PlaySMS version 1.4, specifically in the import.php script. This critical security flaw enables remote code execution through manipulation of the User-Agent HTTP header, demonstrating a classic server-side request forgery vulnerability that can be exploited by attackers to execute arbitrary commands on the target system. The vulnerability stems from insufficient input validation and sanitization of user-supplied data, particularly within the HTTP headers that are processed during file upload operations.
The technical implementation of this vulnerability involves the manipulation of the User-Agent header to include PHP code that gets executed during the file processing phase. When an attacker crafts a malicious User-Agent string containing executable PHP code, the system fails to properly sanitize this input before it is processed, leading to code injection that can result in complete system compromise. This flaw operates under CWE-94, which classifies the vulnerability as an "Improper Control of Generation of Code ('Code Injection')" where the application incorporates untrusted data into executable code without proper validation or sanitization.
The operational impact of this vulnerability is severe, as it allows attackers to execute arbitrary commands with the privileges of the web server process, potentially leading to full system compromise, data exfiltration, and persistence mechanisms. Attackers can leverage this vulnerability to establish reverse shells, escalate privileges, or deploy additional malware on the compromised system. The attack vector is particularly concerning because it requires minimal interaction from the victim and can be automated through standard web scanning tools. This vulnerability aligns with ATT&CK technique T1059.007, which covers "Command and Scripting Interpreter: PowerShell," as the executed code can include PowerShell commands or other system-level instructions.
The exploitation of this vulnerability demonstrates poor input validation practices and inadequate security controls within the web application's file handling mechanisms. The system fails to properly validate file names and headers, allowing malicious payloads to bypass security checks. Organizations running PlaySMS 1.4 should immediately implement mitigations including input validation, header sanitization, and application-level firewalls to prevent exploitation. The vulnerability also highlights the importance of proper secure coding practices and input validation, particularly when handling user-supplied data in web applications. This flaw serves as a reminder of the critical need for proper security testing and code review processes to prevent similar issues in web-based applications. The vulnerability has been addressed in subsequent versions of PlaySMS through proper input sanitization and improved validation mechanisms that prevent the execution of malicious code through HTTP headers.