Nagios Log Server versions prior to 2026R1.0.1 are vulnerable to local privilege escalation due to unsafe interaction between sudo rules and file system permissions. The web server account is granted passwordless sudo access to certain maintenance scripts while also being a member of a group that has write access to the directory containing those scripts. A local attacker running as the web server user can replace one of the permitted scripts with a malicious program and then execute it via sudo, resulting in arbitrary code execution with root privileges.
Weakness
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
Potential Mitigations
- Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
References