lm_sensors: Insecure temporary file creation

Background

lm_sensors is a software package that provides drivers for monitoring the temperatures, voltages, and fans of Linux systems with hardware monitoring devices.

Description

Javier Fernandez-Sanguino Pena has discovered that lm_sensors insecurely creates temporary files with predictable filenames when saving configurations.

Impact

A local attacker could create symbolic links in the temporary file directory, pointing to a valid file somewhere on the filesystem. When the pwmconfig script of lm_sensors is executed, this would result in the file being overwritten with the rights of the user running the script, which typically is the root user.

Workaround

There is no known workaround at this time.

Resolution

All lm_sensors users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=sys-apps/lm_sensors-2.9.1-r1"