CVE-2008-5985 in Epiphany
Summary
by MITRE
Untrusted search path vulnerability in the Python interface in Epiphany 2.22.3, and possibly other versions, allows local users to execute arbitrary code via a Trojan horse Python file in the current working directory, related to a vulnerability in the PySys_SetArgv function (CVE-2008-5983).
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Analysis
by VulDB Data Team • 08/30/2019
The vulnerability described in CVE-2008-5985 represents a critical untrusted search path issue affecting the Epiphany web browser's Python interface version 2.22.3 and potentially other iterations. This flaw stems from improper handling of Python module loading within the browser's execution environment, creating a pathway for local privilege escalation through malicious code injection. The vulnerability specifically exploits the PySys_SetArgv function which is responsible for setting the Python interpreter's argument vector, allowing attackers to manipulate the module search path in ways that could lead to arbitrary code execution. The root cause lies in the browser's failure to properly sanitize or validate the current working directory when loading Python modules, creating an environment where malicious actors can place Trojan horse Python files that will be executed with elevated privileges.
This security weakness operates through a classic path traversal attack vector where an attacker positions a malicious Python script in the current working directory from which Epiphany is launched. When the browser's Python interface attempts to load modules, it searches through the current directory before checking system paths, inadvertently executing the attacker-controlled code. The vulnerability is particularly dangerous because it leverages the trust relationship between the browser and its Python interface, where legitimate Python modules are loaded without proper path validation. This flaw aligns with CWE-426 Untrusted Search Path and CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component, as it demonstrates how insecure path handling can lead to privilege escalation through code injection. The attack requires local system access but can potentially result in complete system compromise when executed by a user with sufficient privileges to launch the browser.
The operational impact of CVE-2008-5985 extends beyond simple code execution to encompass potential privilege escalation and system compromise within the context of local user environments. Attackers could exploit this vulnerability to execute malicious payloads with the privileges of the user running Epiphany, potentially leading to data theft, system modification, or further attack vector establishment. The vulnerability affects not just the specific version mentioned but likely other versions of Epiphany that employ similar Python interface implementations, making it a widespread concern for Linux desktop environments that utilize this browser. This flaw particularly impacts desktop environments where users may not be security-conscious and where the browser is frequently launched from user-controlled directories. The attack scenario typically involves an attacker placing a malicious Python file in a directory where Epiphany is executed, such as the user's home directory or a shared network location, then tricking the user into launching the browser or triggering the Python interface component.
Mitigation strategies for CVE-2008-5985 should focus on both immediate remediation and long-term architectural improvements to prevent similar vulnerabilities. The most effective immediate solution involves updating to patched versions of Epiphany where the Python interface properly validates module paths and implements secure search path handling. System administrators should also implement strict directory permissions and ensure that user directories have appropriate security controls to prevent unauthorized file placement. The vulnerability highlights the importance of following secure coding practices such as those outlined in the OWASP Secure Coding Practices, particularly regarding input validation and path handling. Organizations should consider implementing privilege separation techniques where the browser's Python interface runs with minimal privileges and restricted path access. Additionally, regular security audits of application interfaces and component libraries should be conducted to identify similar untrusted search path vulnerabilities. The ATT&CK framework categorizes this vulnerability under T1068 Privilege Escalation and T1546 Persistence, as it enables attackers to establish persistent access through code execution in trusted locations, emphasizing the need for comprehensive security measures beyond simple patching.