Sudo Flaw Lets Linux Users Run Commands As Root Even When They're Restricted

From Hacker News:

A vulnerability has been discovered in Sudo—one of the most important, powerful, and commonly used utilities that comes as a core command installed on almost every UNIX and Linux-based operating system.

The vulnerability in question is a sudo security policy bypass issue that could allow a malicious user or a program to execute arbitrary commands as root on a targeted Linux system even when the "sudoers configuration" explicitly disallows the root access.

The vulnerability, tracked as CVE-2019-14287 and discovered by Joe Vennix of Apple Information Security, is more concerning because the sudo utility has been designed to let users use their own login password to execute commands as a different user without requiring their password.

What's more interesting is that this flaw can be exploited by an attacker to run commands as root just by specifying the user ID "-1" or "4294967295."

That's because the function which converts user id into its username incorrectly treats -1, or its unsigned equivalent 4294967295, as 0, which is always the user ID of root user.

More info:
https://thehackernews.com/2019/10/linux-sudo-run-as-root-flaw.html