You can bypass Apple OS X security Yosemite and gain administrator privileges using a few lines of code that fit in a tweet.
Yosemite OS, also known as version 10.10, is the last stable version of Apple's operating system, so many will have problems with this vulnerability.
It's all possible thanks to an environment variable called DYLD_PRINT_TO_FILE added to Yosemite by Apple. Clarifies, where in the system files an operating system component called dynamic linker can record error logs.
If the variable is changed by a privileged program, an attacker can arbitrarily modify it archives belonging to the root account, files that can only be changed with administrator rights.[tweet_embed id = 623727538234368000]
These shell commands run whoami to find the username (for example iguru) and then there is "ALL = (ALL) NOPASSWD: ALL". So we have:
ALL = (ALL) NOPASSWD: ALL
Then the results through DYLD_PRINT_TO_FILE are logged and contain the list of users who can obtain root privileges: / etc / sudoers.
This line tells OS X that your user account has the ability to get root permissions without a password.
A privileged program (owned by root) runs the set-uid newgrp - to access root level in the sudoers file.
Finally, with a sudo -s opens an interactive command-line shell, which has root privileges for the user's account thanks to the updated sudoers file.
From there, you can do what you want, modify documents, install malicious software, create new users, or think about anything else.
The vulnerability exists in the latest version of Yosemite, OS X 10.10.4, as well as in the beta version 10.10.5. If you upgrade to El Capitan beta (OS X 10.11), you will be safe as the vulnerability does not exist.
For a temporary solution to affected systems, download and install it SUIDGuard of Esser.