UNIX symbolic link following in Podman - CVE-2019-18466

Detailed vulnerability description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a symlink following issue in libpod (podman) in the host context during a copy operation from the container to the host, because an undesired glob operation occurs. An attacker could create a container image containing particular symlinks that, when copied by a victim user to the host filesystem, may overwrite existing files with others from the host.

Successful exploitation of this vulnerability may result in privilege escalation on the host operating system.

How to mitigate CVE-2019-18466

Sources

• https://access.redhat.com/errata/RHSA-2019:4269
• https://bugzilla.redhat.com/show_bug.cgi?id=1744588
• https://github.com/containers/libpod/commit/5c09c4d2947a759724f9d5aef6bac04317e03f7e
• https://github.com/containers/libpod/compare/v1.5.1...v1.6.0
• https://github.com/containers/libpod/issues/3829