Handle the CVE-2021-3156 Vulnerability

A severe vulnerability has been found in Unix and Linux operating systems, that can affect Smart ID Digital Access component. This article describes how to handle the vulnerability.

This is only a problem if you have added unprivileged users to the system. The default installation does not have any unprivileged users.

An unprivileged user can exploit the vulnerability using sudo, which can cause a heap overflow to elevate privileges to root, without authentication, or even get listed in the sudoers file. 

1. Run this command to see if you have a vulnerable system:
   

   Check if you have a vulnerable system

   CODE

   sudoedit -s /

    

   1. If you have a vulnerable system, the response is 
      

      sudoedit: /: not a regular file

2. Depending on version, enter these commands to handle the vulnerability:

   1. For Digital Access 6.0.0 to 6.0.2
      

      For Digital Access 6.0.0 to 6.0.2

      CODE

      sudo apt update
      sudo apt install sudo=1.8.31-1ubuntu1.2

   2. For Digital Access 5.13.1 - 5.13.5
      

      For Digital Access 5.13.1 to 5.13.5

      CODE

      sudo apt update 
      sudo apt install sudo=1.8.21p2-3ubuntu1.4

3. Run this command again:
   

   Check the system again for vulnerability

   CODE

   sudoedit -s /

   1. The answer shall now be:
      

      Answer if system is not vulnerable

      CODE

      usage: sudoedit [-AknS] [-r role] [-t type] [-C num] [-g group] [-h host] [-p prompt] [-T timeout] [-u user] file ...