The _asn1_extract_der_octet function in lib/decoding.c in GNU Libtasn1 before 4.8, when used without the ASN1_DECODE_FLAG_STRICT_DER flag, allows remote attackers to cause a denial of service (infinite recursion) via a crafted certificate. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-4008
