An issue was discovered in PostgreSQL 12.2 allows attackers to cause a denial of service via repeatedly sending SIGHUP signals. NOTE: this is disputed by the vendor because untrusted users cannot send SIGHUP signals; they can only be sent by a PostgreSQL superuser, a user with pg_reload_conf access, or a user with sufficient privileges at the OS level (the postgres account or the root account).

The xml_parse function in the libxml2 support in the core server component in PostgreSQL 8.3 before 8.3.20, 8.4 before 8.4.13, 9.0 before 9.0.9, and 9.1 before 9.1.5 allows remote authenticated users to determine the existence of arbitrary files or URLs, and possibly obtain file or URL content that triggers a parsing error, via an XML value that refers to (1) a DTD or (2) an entity, related to an XML External Entity (aka XXE) issue.

PostgreSQL 8.4.x before 8.4.11, 9.0.x before 9.0.7, and 9.1.x before 9.1.3 truncates the common name to only 32 characters when verifying SSL certificates, which allows remote attackers to spoof connections when the host name is exactly 32 characters.