USN-8294-1: PostgreSQL vulnerabilities

It was discovered that PostgreSQL did not correctly enforce authorization
for CREATE TYPE. An attacker could possibly use this issue to execute
arbitrary SQL functions. (CVE-2026-6472)

It was discovered that PostgreSQL incorrectly handled large user input in
multiple server features. An attacker could possibly use this issue to
cause PostgreSQL to crash, resulting in a denial of service, or execute
arbitrary code. (CVE-2026-6473)

It was discovered that PostgreSQL incorrectly handled format strings in
the timeofday() function. An attacker could possibly use this issue to
obtain sensitive information. (CVE-2026-6474)

It was discovered that PostgreSQL incorrectly followed symbolic links in
pg_basebackup and pg_rewind. An attacker could possibly use this issue to
overwrite local files and execute arbitrary code. (CVE-2026-6475)

It was discovered that PostgreSQL had an SQL injection vulnerability in
pg_createsubscriber. An attacker could possibly use this issue to execute
arbitrary SQL as a superuser. This issue only affected Ubuntu 25.10 and
Ubuntu 26.04 LTS. (CVE-2026-6476)

It was discovered that PostgreSQL used an unsafe libpq function in large
object operations. An attacker could possibly use this issue to overwrite
client memory and execute arbitrary code. (CVE-2026-6477)

It was discovered that PostgreSQL did not compare MD5-hashed passwords in
constant time. An attacker could possibly use this issue to obtain
sensitive information. (CVE-2026-6478)

It was discovered that PostgreSQL had uncontrolled recursion during SSL and
GSS negotiation. An attacker could possibly use this issue to cause a
denial of service. (CVE-2026-6479)

It was discovered that PostgreSQL incorrectly handled array length
mismatches in pg_restore_attribute_stats(). An attacker could possibly use
this issue to obtain sensitive information. This issue only affected Ubuntu
26.04 LTS. (CVE-2026-6575)

It was discovered that PostgreSQL had a stack buffer overflow in the refint
module. An attacker could use this issue to cause PostgreSQL to crash,
resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2026-6637)

It was discovered that PostgreSQL had an SQL injection vulnerability in
logical replication REFRESH PUBLICATION. An attacker could possibly use
this issue to execute arbitrary SQL. This issue only affected Ubuntu 24.04
LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-6638)