You can skip it better safety του λειτουργικού της Apple OS X Yosemite και να αποκτήσετε δικαιώματα διαχειριστή χρησιμοποιώντας λίγες γραμμές κώδικα που χωράνε σε ένα 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.
It's all possible thanks to an environment variable called DYLD_PRINT_TO_FILE added to Yosemite by Apple. It clarifies, where in the system files a component of the operating system called dynamic linker can record error messages (error logs).
If the variable is changed by a privileged program, an attacker can arbitrarily modify it archives belonging to account root, 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.
