Integer overflow in the _IO_wstr_overflow function in libio/wstrops.c in the GNU C Library (aka glibc or libc6) before 2.22 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via vectors related to computing a size in bytes, which triggers a heap-based buffer overflow. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-8983