Re: [ANNOUNCE] IMPORTANT: two new PostgreSQL security problems

> Two serious security errors have been found in PostgreSQL 7.3 and newer
> releases.  These errors at least allow an unprivileged database user to
> crash the backend process, and may make it possible for an unprivileged
> user to gain the privileges of a database superuser.
> 
> We are currently preparing new releases that will correct these problems
> in freshly initdb'd installations.  However, because these problems are
> really incorrect system catalog entries, updating to a new release will
> NOT by itself solve the problems in an existing installation.  Instead,
> it is necessary for the database administrator to fix the catalog entries
> manually, as described below.  We are releasing this advisory to encourage
> administrators of PostgreSQL installations to perform these fixes as soon
> as possible.
> 
> 
> Character conversion vulnerability
> ----------------------------------
> 
> The more severe of the two errors is that the functions that support
> client-to-server character set conversion can be called from SQL commands
> by unprivileged users, but these functions are not designed to be safe
> against malicious choices of argument values.  This problem exists in
> PostgreSQL 7.3.* through 8.0.*.  The recommended fix is to disable public
> EXECUTE access for these functions.  This does not affect normal usage of
> the functions for character set conversion, but it will prevent misuse.
[snip]

I apologize as the original developer for CREATE CONVERSION. I should
have made these functions only accessible by privileged users when I
developed it.
--
Tatsuo Ishii