Ubuntu 18.10, 18.04 LTS: USN-3816-1 Moderate: Systemd Exploits

ubuntu

November 12, 2018

Several security issues were fixed in systemd.

Summary

Several security issues were fixed in systemd.

Software Description:

- systemd: system and service manager

Details:

Jann Horn discovered that unit_deserialize incorrectly handled status messages

above a certain length. A local attacker could potentially exploit this via

NotifyAccess to inject arbitrary state across re-execution and obtain root

privileges. (CVE-2018-15686)

Jann Horn discovered a race condition in chown_one(). A local attacker

could potentially exploit this by setting arbitrary permissions on certain

files to obtain root privileges. This issue only affected Ubuntu 18.04 LTS

and Ubuntu 18.10. (CVE-2018-15687)

It was discovered that systemd-tmpfiles mishandled symlinks in

non-terminal path components. A local attacker could potentially exploit

this by gaining ownership of certain files to obtain root privileges. This

issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2018-6954)

Topics Covered

security advisory moderate local privilege escalation Ubuntu symlink attack systemd

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 18.10:
  systemd                         239-7ubuntu10.3

Ubuntu 18.04 LTS:
  systemd                         237-3ubuntu10.6

Ubuntu 16.04 LTS:
  systemd                         229-4ubuntu21.8

After a standard system update you need to reboot your computer to make
all the necessary changes.