Red Hat Security Advisory: glibc security, bug fix, and enhancement update

Moderate

elf/dl-load.c in the GNU C Library (aka glibc or libc6) 2.19 through 2.26 mishandles RPATH and RUNPATH containing $ORIGIN for a privileged (setuid or AT_SECURE) 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.

CWE-470 - Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')

An integer overflow in the implementation of the posix_memalign in memalign functions in the GNU C Library (aka glibc or libc6) 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.

CWE-190 - Integer Overflow or Wraparound