A buffer overflow in glibc 2.5 (released on September 29, 2006) and can be triggered through the LD_LIBRARY_PATH environment variable. Please note that many versions of glibc are not vulnerable to this issue if patched for CVE-2017-1000366.
In glibc 2.26 and earlier there is confusion in the usage of getcwd() by realpath() which can be used to write before the destination buffer leading to a buffer underflow and potential code execution.
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.
The malloc function in the GNU C Library (aka glibc or libc6) 2.26 could return a memory block that is too small if an attempt is made to allocate an object whose size is close to SIZE_MAX, potentially leading to a subsequent heap overflow. This occurs because the per-thread cache (aka tcache) feature enables a code path that lacks an integer overflow check.
The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27 contains a buffer overflow during unescaping of user names with the ~ operator.
The GNU C Library (aka glibc or libc6) before 2.27 contains an off-by-one error leading to a heap-based buffer overflow in the glob function in glob.c, related to the processing of home directories using the ~ operator followed by a long string.
The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27, when invoked with GLOB_TILDE, could skip freeing allocated memory when processing the ~ operator with a long user name, potentially leading to a denial of service (memory leak).
Use-after-free vulnerability in the clntudp_call function in sunrpc/clnt_udp.c in the GNU C Library (aka glibc or libc6) before 2.26 allows remote attackers to have unspecified impact via vectors related to error path.
The DNS stub resolver in the GNU C Library (aka glibc or libc6) before version 2.26, when EDNS support is enabled, will solicit large UDP responses from name servers, potentially simplifying off-path DNS spoofing attacks due to IP fragmentation.