USN-3816-3: systemd regression
- Canonical Ubuntu 16.04
USN-3816-1 fixed vulnerabilities in systemd. The fix for CVE-2018-6954 caused a regression in systemd-tmpfiles when running Ubuntu inside a container on some older kernels. This issue only affected Ubuntu 16.04 LTS. In order to continue to support this configuration, the fixes for CVE-2018-6954 have been reverted.
We apologize for the inconvenience.
Original advisory 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)
Affected Cloud Foundry Products and Versions
Severity is unknown unless otherwise noted.
- Cloud Foundry BOSH xenial-stemcells are vulnerable, including:
- 170.x versions prior to 170.12
- 97.x versions prior to 97.39
- All other stemcells not listed.
Users of affected products are strongly encouraged to follow one of the mitigations below:
- The Cloud Foundry project recommends upgrading the following BOSH xenial-stemcells:
- Upgrade 170.x versions to 170.12
- Upgrade 97.x versions to 97.39
- All other stemcells should be upgraded to the latest version available on bosh.io.