contrib/pgcrypto in PostgreSQL before 9.0.20, 9.1.x before 9.1.16, 9.2.x before 9.2.11, 9.3.x before 9.3.7, and 9.4.x before 9.4.2 uses different error responses when an incorrect key is used, which makes it easier for attackers to obtain the key via a brute force attack.

The snprintf implementation in PostgreSQL before 9.0.20, 9.1.x before 9.1.16, 9.2.x before 9.2.11, 9.3.x before 9.3.7, and 9.4.x before 9.4.2 does not properly handle system-call errors, which allows attackers to obtain sensitive information or have other unspecified impact via unknown vectors, as demonstrated by an out-of-memory error.

PostgreSQL versions 10.x before 10.9 and versions 11.x before 11.4 are vulnerable to a stack-based buffer overflow. Any authenticated user can overflow a stack-based buffer by changing the user's own password to a purpose-crafted value. This often suffices to execute arbitrary code as the PostgreSQL operating system account.

A vulnerability was found in libpq, the default PostgreSQL client library where libpq failed to properly reset its internal state between connections. If an affected version of libpq was used with "host" or "hostaddr" connection parameters from untrusted input, attackers could bypass client-side connection security features, obtain access to higher privileged connections or potentially cause other impact through SQL injection, by causing the PQescape() functions to malfunction. Postgresql versions before 10.5, 9.6.10, 9.5.14, 9.4.19, and 9.3.24 are affected.

Invalid json_populate_recordset or jsonb_populate_recordset function calls in PostgreSQL 10.x before 10.1, 9.6.x before 9.6.6, 9.5.x before 9.5.10, 9.4.x before 9.4.15, and 9.3.x before 9.3.20 can crash the server or disclose a few bytes of server memory.

PostgreSQL versions before 9.4.13, 9.5.8 and 9.6.4 are vulnerable to authorization flaw allowing remote authenticated attackers with no privileges on a large object to overwrite the entire contents of the object, resulting in a denial of service.

PostgreSQL before 9.1.23, 9.2.x before 9.2.18, 9.3.x before 9.3.14, 9.4.x before 9.4.9, and 9.5.x before 9.5.4 might allow remote authenticated users with the CREATEDB or CREATEROLE role to gain superuser privileges via a (1) " (double quote), (2) \ (backslash), (3) carriage return, or (4) newline character in a (a) database or (b) role name that is mishandled during an administrative operation.

PostgreSQL before 9.1.23, 9.2.x before 9.2.18, 9.3.x before 9.3.14, 9.4.x before 9.4.9, and 9.5.x before 9.5.4 allow remote authenticated users to cause a denial of service (NULL pointer dereference and server crash), obtain sensitive memory information, or possibly execute arbitrary code via (1) a CASE expression within the test value subexpression of another CASE or (2) inlining of an SQL function that implements the equality operator used for a CASE expression involving values of different types.

PostgreSQL before 9.1.20, 9.2.x before 9.2.15, 9.3.x before 9.3.11, 9.4.x before 9.4.6, and 9.5.x before 9.5.1 does not properly restrict access to unspecified custom configuration settings (GUCS) for PL/Java, which allows attackers to gain privileges via unspecified vectors.

PostgreSQL before 9.1.20, 9.2.x before 9.2.15, 9.3.x before 9.3.11, 9.4.x before 9.4.6, and 9.5.x before 9.5.1 allows remote attackers to cause a denial of service (infinite loop or buffer overflow and crash) via a large Unicode character range in a regular expression.