CVE-2018-1113 Auth bypass in setup
Adding nologin to /etc/shells allows users with that shell to bypass authentication checks in daemons relying on pam_shells.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2018-1113?
CVE-2018-1113 is a medium-severity authentication bypass vulnerability in Redhat Enterprise Linux Desktop, published on 2 Jul 2018. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
setup before version 2.11.4-1.fc28 in Fedora and Red Hat Enterprise Linux added /sbin/nologin and /usr/sbin/nologin to /etc/shells. This violates security assumptions made by pam_shells and some daemons which allow access based on a user's shell being listed in /etc/shells. Under some circumstances, users which had their shell changed to /sbin/nologin could still access the system.
Which versions are affected by CVE-2018-1113?
It affects 4 products.
Linux distribution packages (4)
setup Red Hat:enterprise_linux:7::client | All versions | 0:2.8.71-10.el7 |
setup Red Hat:enterprise_linux:7::computenode | All versions | 0:2.8.71-10.el7 |
setup Red Hat:enterprise_linux:7::server | All versions | 0:2.8.71-10.el7 |
setup Red Hat:enterprise_linux:7::workstation | All versions | 0:2.8.71-10.el7 |
Products include Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Workstation, Redhat Setup.
How do I fix CVE-2018-1113?
Apply the vendor's patch.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2018-1113 being exploited?
There is no known exploitation of CVE-2018-1113 in the wild and no public exploit code.
Other vulnerabilities in Redhat Enterprise Linux Desktop
Sources
Also known as GHSA-pj9f-pvw9-ffjc, RHSA-2018:3249.