TLDR: A misconfigured PATH environment variable can lead to security risks, execution errors, and inefficient workflows. The PATH variable, a critical component in Unix-based systems since their development in the 1970s, dictates where the system searches for executables. Issues such as missing directories, incorrect order, or inclusion of untrusted paths can disrupt software functionality and expose systems to potential exploits.
https://en.wikipedia.org/wiki/PATH_(variable)
One common issue with a misconfigured PATH variable is the omission of essential directories, such as `/usr/bin` or `/usr/local/bin`, leading to “command not found” errors for standard tools. Another problem is placing untrusted directories, such as writable user folders, earlier in the PATH, which attackers can exploit by inserting malicious executables. Similarly, redundant or incorrect entries in the PATH can slow down command execution as the system unnecessarily searches non-existent or irrelevant locations.
https://pubs.opengroup.org/onlinepubs/9699919799/
To address these issues, administrators and users should carefully review and standardize the PATH variable. Essential directories should be included in a secure order, starting with trusted system paths and excluding untrusted locations. Regular audits and tools like env can help identify misconfigurations. By ensuring the PATH variable is concise, correctly ordered, and free from vulnerabilities, systems maintain optimal performance and security.