DISPUTED In the GNU C Library (aka glibc or libc6) through 2.29, checkdstlimitscalcpos1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(|)(\\1\\1)' in grep, a different issue than CVE-2018-20796. NOTE: the software maintainer disputes that this is a vulnerability because the behavior occurs only with a crafted pattern.