A new Linux kernel vulnerability disclosed on Wednesday allows an unprivileged local attacker to escalate their privileges on a targeted system. Red Hat said it was aware of an exploit in the wild.

The vulnerability, discovered by Phil Oester, was sarcastically dubbed by some people “Dirty COW” due to the fact that it’s caused by a race condition in the way the Linux kernel’s memory subsystem handles copy-on-write (COW) breakage of private read-only memory mappings.