CVE-2013-7426 in Kamailio
Summary
by MITRE
Insecure Temporary file vulnerability in /tmp/kamailio_fifo in kamailio 4.0.1.
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Analysis
by VulDB Data Team • 11/11/2019
The CVE-2013-7426 vulnerability represents a critical insecure temporary file flaw in the kamailio SIP server version 4.0.1, specifically within the /tmp/kamailio_fifo component. This vulnerability stems from improper handling of temporary files during the initialization and operation of the kamailio service, creating a potential attack vector for privilege escalation and system compromise. The issue manifests when the application creates temporary files in the /tmp directory without adequate security measures to prevent unauthorized access or manipulation by malicious actors.
The technical flaw occurs due to insufficient permissions and security controls on temporary file creation within the kamailio_fifo mechanism. When kamailio initializes and creates temporary files in the /tmp directory, these files are often created with predictable names and insufficient access controls. This allows local attackers to create symbolic links or manipulate the temporary files before the legitimate application processes them, enabling privilege escalation attacks. The vulnerability is particularly dangerous because it operates at the system level where kamailio may run with elevated privileges, potentially allowing attackers to execute arbitrary code with the same privileges as the kamailio process.
This vulnerability has significant operational impact within network infrastructure environments where kamailio serves as a SIP proxy or server. Attackers exploiting this flaw can gain unauthorized access to systems running vulnerable kamailio versions, potentially leading to complete system compromise, data exfiltration, or disruption of communication services. The attack surface is particularly concerning in environments where kamailio handles sensitive telecommunications data or serves as a critical component in VoIP infrastructure, as the compromise could affect business continuity and security posture. The vulnerability also aligns with attack patterns described in the ATT&CK framework under privilege escalation techniques and persistence mechanisms.
Mitigation strategies for CVE-2013-7426 involve immediate patching of affected kamailio installations to versions that properly implement secure temporary file handling. Organizations should also implement proper file system permissions and access controls for temporary directories, ensuring that temporary files are created with appropriate security attributes and are not accessible to unauthorized users. System administrators should consider implementing monitoring and alerting for suspicious temporary file creation patterns and conduct regular security assessments of telecommunication infrastructure. The vulnerability demonstrates the importance of secure coding practices and proper file handling as outlined in CWE-377 and CWE-378, which address insecure temporary file creation and improper file permissions respectively. Additionally, organizations should follow the principle of least privilege and implement network segmentation to limit the potential impact of such vulnerabilities in their infrastructure.