postgresql: PostgreSQL libpq: Buffer overflow allows server superuser to overwrite client stack memory

A flaw was found in PostgreSQL libpq. A server superuser can exploit a buffer overflow vulnerability in the PQfn function, which is used by client functions such as loexport, loread, lolseek64, and lotell64. This allows the superuser to send an arbitrarily large response, overwriting the client's...

Important: libpq

Issue Overview: Use of inherently dangerous function PQfn..., resultisint=0, ... in PostgreSQL libpq loexport, loread, lolseek64, and lotell64 functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets, PQfn..., resultisint=0, ... stores...

Use of Inherently Dangerous Function

Overview Affected versions of this package are vulnerable to Use of Inherently Dangerous Function via the PQfn function when called with resultisint=0 in the loexport, loread, lolseek64, and lotell64 functions. An attacker can overwrite client stack memory with arbitrary data by sending a special...

CVE-2026-6477

Use of inherently dangerous function PQfn..., resultisint=0, ... in PostgreSQL libpq loexport, loread, lolseek64, and lotell64 functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets, PQfn..., resultisint=0, ... stores arbitrary-lengt...

CVE-2026-6477 PostgreSQL libpq lo_* functions let server superuser overwrite client stack memory

Use of inherently dangerous function PQfn..., resultisint=0, ... in PostgreSQL libpq loexport, loread, lolseek64, and lotell64 functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets, PQfn..., resultisint=0, ... stores arbitrary-lengt...

CVE-2026-6477

The CVE describes a vulnerability in PostgreSQL libpq where PQfn(..., result_is_int=0, ...) can cause an arbitrary, server-supplied data payload to be written into a client stack memory buffer by the server superuser. Affected components include libpq functions lo_export(), lo_read(), lo_lseek64(...