It was discovered systemd does not correctly check the content of PIDFile files before using it to kill processes. When a service is run from an unprivileged user (e.g. User field set in the service file), a local attacker who is able to write to the PIDFile of the mentioned service may use this flaw to trick systemd into killing other services and/or privileged processes. Versions before v237 are vulnerable.
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Systemd | Systemd_project | * | 237 (excluding) |
| Red Hat Ansible Tower 3.4 for RHEL 7 | RedHat | ansible-tower-34/ansible-tower-memcached:1.4.15-28 | * |
| Red Hat Ansible Tower 3.4 for RHEL 7 | RedHat | ansible-tower-35/ansible-tower-memcached:1.4.15-28 | * |
| Red Hat Ansible Tower 3.4 for RHEL 7 | RedHat | ansible-tower-37/ansible-tower-memcached-rhel7:1.4.15-28 | * |
| Red Hat Enterprise Linux 7 | RedHat | systemd-0:219-67.el7 | * |
| Systemd | Ubuntu | upstream | * |
| Systemd | Ubuntu | xenial | * |
New weaknesses can be exposed because running with extra privileges, such as root or Administrator, can disable the normal security checks being performed by the operating system or surrounding environment. Other pre-existing weaknesses can turn into security vulnerabilities if they occur while operating at raised privileges. Privilege management functions can behave in some less-than-obvious ways, and they have different quirks on different platforms. These inconsistencies are particularly pronounced if you are transitioning from one non-root user to another. Signal handlers and spawned processes run at the privilege of the owning process, so if a process is running as root when a signal fires or a sub-process is executed, the signal handler or sub-process will operate with root privileges.