Red Hat Security Advisory 2015-2111-07 – The grep utility searches through textual input for lines that contain a match to a specified pattern and then prints the matching lines. The GNU grep utilities include grep, egrep, and fgrep. A heap-based buffer overflow flaw was found in the way grep processed certain pattern and text combinations. An attacker able to trick a user into running grep on specially crafted input could use this flaw to crash grep or, potentially, read from uninitialized memory.