1DBLINK_CONNECT_U(3) PostgreSQL 11.6 Documentation DBLINK_CONNECT_U(3)
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6 dblink_connect_u - opens a persistent connection to a remote database,
7 insecurely
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10 dblink_connect_u(text connstr) returns text
11 dblink_connect_u(text connname, text connstr) returns text
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14 dblink_connect_u() is identical to dblink_connect(), except that it
15 will allow non-superusers to connect using any authentication method.
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17 If the remote server selects an authentication method that does not
18 involve a password, then impersonation and subsequent escalation of
19 privileges can occur, because the session will appear to have
20 originated from the user as which the local PostgreSQL server runs.
21 Also, even if the remote server does demand a password, it is possible
22 for the password to be supplied from the server environment, such as a
23 ~/.pgpass file belonging to the server's user. This opens not only a
24 risk of impersonation, but the possibility of exposing a password to an
25 untrustworthy remote server. Therefore, dblink_connect_u() is initially
26 installed with all privileges revoked from PUBLIC, making it
27 un-callable except by superusers. In some situations it may be
28 appropriate to grant EXECUTE permission for dblink_connect_u() to
29 specific users who are considered trustworthy, but this should be done
30 with care. It is also recommended that any ~/.pgpass file belonging to
31 the server's user not contain any records specifying a wildcard host
32 name.
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34 For further details see dblink_connect().
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38PostgreSQL 11.6 2019 DBLINK_CONNECT_U(3)