CVE-2024-35235

OpenPrinting CUPS is an open source printing system for Linux and other
Unix-like operating systems. In versions 2.4.8 and earlier, when starting
the cupsd server with a Listen configuration item pointing to a symbolic
link, the cupsd process can be caused to perform an arbitrary chmod of the
provided argument, providing world-writable access to the target. Given
that cupsd is often running as root, this can result in the change of
permission of any user or system files to be world writable. Given the
aforementioned Ubuntu AppArmor context, on such systems this vulnerability
is limited to those files modifiable by the cupsd process. In that specific
case it was found to be possible to turn the configuration of the Listen
argument into full control over the cupsd.conf and cups-files.conf
configuration files. By later setting the User and Group arguments in
cups-files.conf, and printing with a printer configured by PPD with a
FoomaticRIPCommandLine argument, arbitrary user and group (not root)
command execution could be achieved, which can further be used on Ubuntu
systems to achieve full root command execution. Commit
ff1f8a623e090dee8a8aadf12a6a4b25efac143d contains a patch for the issue.

Notes