A buffer overflow has been discovered in the GNU C Library in the __mempcpy_avx512_no_vzeroupper function when particular conditions are met. An attacker could use this vulnerability to cause a denial of service or potentially execute code.elf/dl-load.c in the GNU C Library 2.19 through 2.26 mishandles RPATH and RUNPATH containing $ORIGIN for a privileged program, which allows local users to gain privileges via a Trojan horse library in the current working directory, related to the fillin_rpath and decompose_rpath functions. This is associated with misinterpretion of an empty RPATH/RUNPATH token as the "./" directory. NOTE: this configuration of RPATH/RUNPATH for a privileged program is apparently very uncommon; most likely, no such program is shipped with any common Linux distribution.stdlib/canonicalize.c in the GNU C Library 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.An integer overflow in the implementation of the posix_memalign in memalign functions in the GNU C Library 2.26 and earlier could cause these functions to return a pointer to a heap area that is too small, potentially leading to heap corruption.