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.
Exploitability
AV:NAC:LAu:NImpact
C:PI:PA:P7.5/AV:N/AC:L/Au:N/C:P/I:P/A:P