CVE-2026-6477

Name of the Vulnerable Software and Affected Versions PostgreSQL versions prior to 18.4 PostgreSQL versions prior to 17.10 PostgreSQL versions prior to 16.14 PostgreSQL versions prior to 15.18 PostgreSQL versions prior to 14.23

Description The use of the dangerous function PQfn(..., result is int=0, ...) within the libpq lo export(), lo read(), lo lseek64(), and lo tell64() functions allows a server superuser to overwrite a client stack buffer with an arbitrarily-large response. This occurs because the function stores server-determined data of arbitrary length into a buffer of unspecified size. Consequently, since the lo export command in psql and pg dump utilize lo read(), a server superuser can overwrite the stack memory of psql or pg dump.

Recommendations Update to version 18.4 or later. Update to version 17.10 or later. Update to version 16.14 or later. Update to version 15.18 or later. Update to version 14.23 or later.