This release contains a variety of fixes from 14.0. For information about new features in major release 14, see Section E.2.
A dump/restore is not required for those running 14.X.
However, note that installations using physical replication should update standby servers before the primary server, as explained in the third changelog entry below.
Also, several bugs have been found that may have resulted in corrupted indexes, as explained in the next several changelog entries. If any of those cases apply to you, it's recommended to reindex possibly-affected indexes after updating.
Make the server reject extraneous data after an SSL or GSS encryption handshake (Tom Lane)
A man-in-the-middle with the ability to inject data into the TCP connection could stuff some cleartext data into the start of a supposedly encryption-protected database session. This could be abused to send faked SQL commands to the server, although that would only work if the server did not demand any authentication data. (However, a server relying on SSL certificate authentication might well not do so.)
The PostgreSQL Project thanks Jacob Champion for reporting this problem. (CVE-2021-23214)
Make libpq reject extraneous data after an SSL or GSS encryption handshake (Tom Lane)
A man-in-the-middle with the ability to inject data into the TCP connection could stuff some cleartext data into the start of a supposedly encryption-protected database session. This could probably be abused to inject faked responses to the client's first few queries, although other details of libpq's behavior make that harder than it sounds. A different line of attack is to exfiltrate the client's password, or other sensitive data that might be sent early in the session. That has been shown to be possible with a server vulnerable to CVE-2021-23214.
The PostgreSQL Project thanks Jacob Champion for reporting this problem. (CVE-2021-23222)
Fix physical replication for cases where the primary crashes after shipping a WAL se
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