CVE-2005-2657 in common-lisp-controller
Summary
by MITRE
unknown vulnerability in common-lisp-controller 4.18 and earlier allows local users to gain privileges by compiling arbitrary code in the cache directory which is executed by another user if the user has not run common lisp before.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/09/2019
The vulnerability described in CVE-2005-2657 represents a privilege escalation issue within the common-lisp-controller software version 4.18 and earlier. This flaw exists in the way the system handles code compilation and execution within the cache directory, creating a dangerous condition where local users can manipulate the system's behavior through carefully crafted code injection. The vulnerability specifically targets the installation and execution phases of Common Lisp applications, where the system caches compiled code for performance optimization. When users run Common Lisp applications for the first time, the system creates cache files that are subsequently executed by other users who may have already run the software, creating a persistent vector for privilege elevation.
The technical mechanism behind this vulnerability involves the improper handling of cache directory permissions and execution contexts. The common-lisp-controller application creates cache files in a directory that may be writable by local users, allowing them to compile and place malicious code within this location. When other users subsequently execute Common Lisp applications, the system loads and runs these cached files without sufficient validation or privilege checks. This design flaw creates a race condition and privilege escalation opportunity where a local attacker can place malicious compiled code in the cache directory and have it executed by other users with higher privileges or different user contexts.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it enables persistent backdoor access and system compromise. An attacker with local access can compile malicious Common Lisp code that executes with the privileges of other users who have already run Common Lisp applications. This creates a sophisticated attack vector where the compromise can spread organically through user interactions with the Common Lisp environment, potentially affecting multiple users on the same system. The vulnerability is particularly dangerous because it operates silently without requiring elevated privileges initially, allowing attackers to establish footholds that can later be leveraged for more extensive system compromise.
The weakness in this vulnerability aligns with CWE-276, which addresses improper privileges on resources, and CWE-73, which covers external control of filename or path. Additionally, this vulnerability maps to ATT&CK technique T1068, which involves exploiting vulnerabilities to elevate privileges, and T1548.001, which covers abuse of system privileges. The attack pattern follows the typical privilege escalation methodology where an attacker exploits a weakness in file system permissions and execution contexts to gain unauthorized access to elevated privileges. Organizations should implement strict file system permissions on cache directories, ensure proper user isolation during code compilation, and consider implementing additional validation mechanisms for cached code execution. Regular system auditing and monitoring of cache directory modifications can help detect potential exploitation attempts, while application sandboxing and privilege separation can mitigate the impact of successful attacks.