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: postgresql

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...

PostgreSQL libpq lo_* functions let server superuser overwrite client stack memory

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PT-2026-40922

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=...

Vulnerability in client (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...