A major security breach affecting the Linux ecosystem was fixed overnight in Sudo, an application that allows administrators to grant restricted root access to other users.
Η vulnerability, which has as an identifier the CVE-2021-3156, better known as "Baron Samedit", was discovered by security company Qualys two weeks ago. Fixed last night with the release of Sudo v1.9.5p2 (update immediately).
In a simple explanation provided by the Sudo team, the Baron Samedit bug can be exploited by an attacker who has gained access to a low-privileged account to gain root access, even if the account is not listed in /etc/sudoers – a configuration file that controls which users are allowed access to commands su or sudo.
For technical details see reference of Qualys or below video.
While two other Sudo security vulnerabilities have been uncovered in the last two years, the error being uncovered today is far more dangerous.
The two previous bugs, CVE-2019-14287 and CVE-2019-18634, were difficult to exploit because they required complex and non-standard sudo settings.
Things are different for the bug revealed today, because it affects all Sudo installations where there are sudoers (/ etc / sudoers) - which is usually found on most default Linux installations - Sudo.
