| Description: | A flaw was found affecting the Linux kernel before version 4.17. By mmap()ing a FUSE-backed file onto a process's memory containing command line arguments (or environment strings), an attacker can cause utilities from psutils or procps (such as ps, w) or any other program which makes a read() call to the /proc//cmdline (or /proc//environ) files to block indefinitely (denial of service) or for some controlled time (as a synchronization primitive for other attacks). It was discovered that the procfs filesystem did not properly handle processes mapping some memory elements onto files. A local attacker could use this to block utilities that examine the procfs filesystem to report operating system state, such as ps(1).
|