FreeBSD : Xorg server -- two vulnerabilities in X server lock handling code (8441957c-f9b4-11e0-a78a-bcaec565249c)
Low Nessus Plugin ID 56548
SynopsisThe remote FreeBSD host is missing a security-related update.
DescriptionMatthieu Herrb reports :
It is possible to deduce if a file exists or not by exploiting the way that Xorg creates its lock files. This is caused by the fact that the X server is behaving differently if the lock file already exists as a symbolic link pointing to an existing or non-existing file.
It is possible for a non-root user to set the permissions for all users on any file or directory to 444, giving unwanted read access or causing denies of service (by removing execute permission). This is caused by a race between creating the lock file and setting its access modes.
SolutionUpdate the affected package.