The mtree bidder in libarchive 3.2.1 does not keep track of line sizes when extending the read-ahead, which allows remote attackers to cause a denial of service (crash) via a crafted file, which triggers an invalid read in the (1) detect_form or (2) bid_entry function in libarchive/archive_read_support_format_mtree.c. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8688