nginx 0.5.6 through 1.7.4, when using the same shared ssl_session_cache or ssl_session_ticket_key for multiple servers, can reuse a cached SSL session for an unrelated context, which allows remote attackers with certain privileges to conduct "virtual host confusion" attacks.
The default configuration of nginx, possibly 1.3.13 and earlier, uses world-readable permissions for the (1) access.log and (2) error.log files, which allows local users to obtain sensitive information by reading the files.
nginx/Windows 1.3.x before 1.3.1 and 1.2.x before 1.2.1 allows remote attackers to bypass intended access restrictions and access restricted files via (1) a trailing . (dot) or (2) certain "$index_allocation" sequences in a request.