The TIFFFetchNormalTag function in LibTiff 4.0.6 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by setting the tags TIFF_SETGET_C16ASCII or TIFF_SETGET_C32_ASCII to values that access 0-byte arrays. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-9297. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-9448
