stdlib/canonicalize.c in the GNU C Library (aka glibc or libc6) 2.27 and earlier, when processing very long pathname arguments to the realpath function, could encounter an integer overflow on 32-bit architectures, leading to a stack-based buffer overflow and, potentially, arbitrary code execution.
https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
https://usn.ubuntu.com/4416-1/
https://sourceware.org/bugzilla/show_bug.cgi?id=22786
https://security.netapp.com/advisory/ntap-20190401-0001/
https://access.redhat.com/errata/RHSA-2018:3092