You can skip the security of the Apple OS X Yosemite operating system and gain administrative rights by using a few lines of code that fit into a tweet.
The functional Yosemite, also known as 10.10, is the latest stable version of Apple's operating system, so many will have problems with this vulnerability.
The error that can be exploited by malicious software and hackers to gain complete control of the computer, documented by well-known researcher Stefan Esser.
Everything is possible thanks to an environment variable called DYLD_PRINT_TO_FILE added to Yosemite by Apple. It specifies that within the file system an element of the operating system called dynamic linker can record error logs.
If the variable is changed with a privileged program, an attacker can arbitrarily modify files belonging to the root account, files whose change is allowed only with administrator privileges.[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.