PostgreSQL -- libpq retains an error message from man-in-the-middle

PostgreSQL project reports:

Client use of server error message in PostgreSQL allows a server not trusted under current SSL or GSS settings to furnish arbitrary non-NUL bytes to the libpq application. For example, a man-in-the-middle attacker could send a long error message that a human or screen-scraper user of psql mistakes for valid query results. This is probably not a concern for clients where the user interface unambiguously indicates the boundary between one error message and other text.

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