Title: BestCrypt Arbitrary Privileged Program Execution Vulnerability
Severity: HIGH
Description:
BestCrypt is an encryption product that allows users to create encrypted loopback filesystems.
A vulnerability exists in the 'bctool' command-line interface program used with BestCrypt. When 'fsck' is executed for a specific filesystem type, it attempts to execute the 'fsck' utility appropriate for the specified filesystem. It does so relying on the PATH environment variable.
Environment variables, such as PATH, can be user-defined to arbitrary values. It is dangerous for programs which run with enhanced privileges to rely on PATH to locate executables, as it can result in the execution of malicious 'replacement' utilities placed deliberately in the PATH.
An attacker can create a malicious fsck executable, such as 'fsck.hello' (for filesystem type 'hello'), and have it executed by 'fsck' as root by placing it in PATH. When 'fsck' (executed by setuid 'bctool') attempts to execute 'fsck.hello', it will execute the malicious executable created by the attacker.
Because the 'bctool' is installed setuid root by default, it may be possible for local users to execute arbitrary executables with elevated privileges.
Affected Products:
- Jetico BestCrypt 0.7.0
References:
- Jetico: Jetico Homepage
Juniper Networks provides this content via a wide variety of sources and production methods. If notified of errors or omissions in the content of this page, Juniper Networks, at its discretion, will modify or remove the page or leave the content as is, depending on various factors including but not limited to the reputation and authority of the party providing the notification. Please use the contact information displayed elsewhere on this page to report any errors or omissions regarding the content on this page.
