Linux users should immediately patch a serious vulnerability to the sudo command that, if exploited, can allow unprivileged users gain root privileges on the host machine.
Called Baron Samedit, the flaw has been “hiding in plain sight” for about 10 years, and was discovered earlier this month by researchers at Qualys and reported to sudo developers, who came up with patches Jan. 19, according to a Qualys blog. (The blog includes a video of the flaw being exploited.)
A new version of sudo—sudo v1.9.5p2—has been created to patch the problem, and notifications have been posted for many Linux distros including Debian, Fedora, Gentoo, Ubuntu, and SUSE, according to Qualys.
According to the common vulnerabilities and exposures (CVE) description of Baron Samedit (CVE-2021-3156), the flaw can be exploited “via ‘sudoedit -s’ and a command-line argument that ends with a single backslash character.”
According to Qualys, the flaw was introduced in July 2011 and affects legacy versions from 1.8.2 to 1.8.31p2 as well as default configurations of versions from 1.9.0 to 1.9.5p1.