PostgreSQL 8.1 and probably later versions, when local trust authentication is enabled and the Database Link library (dblink) is installed, allows remote attackers to access arbitrary accounts and execute arbitrary SQL queries via a dblink host parameter that proxies the connection from 127.0.0.1.
Untrusted search path vulnerability in PostgreSQL before 7.3.19, 7.4.x before 7.4.17, 8.0.x before 8.0.13, 8.1.x before 8.1.9, and 8.2.x before 8.2.4 allows remote authenticated users, when permitted to call a SECURITY DEFINER function, to gain the privileges of the function owner, related to "search_path settings."