CVE-2026-6477

Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-large response. Like gets(), PQfn(..., result_is_int=0, ...) stores arbitrary-length, server-determined data into a buffer of unspecified size. Because both the \lo_export command in psql and pg_dump call lo_read(), the server superuser can overwrite pg_dump or psql stack memory. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.postgresql.org/support/security/CVE-2026-6477/	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:postgresql:postgresql::::::::
	cpe:2.3:a:postgresql:postgresql::::::::
	cpe:2.3:a:postgresql:postgresql::::::::
	cpe:2.3:a:postgresql:postgresql::::::::
	cpe:2.3:a:postgresql:postgresql::::::::

History

18 May 2026, 15:03

Type	Values Removed	Values Added
References	~~() https://www.postgresql.org/support/security/CVE-2026-6477/ -~~	() https://www.postgresql.org/support/security/CVE-2026-6477/ - Patch, Vendor Advisory
First Time		Postgresql Postgresql postgresql
CPE		cpe:2.3:a:postgresql:postgresql::::::::

14 May 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-14 14:16

Updated : 2026-05-18 15:03

NVD link : CVE-2026-6477

Mitre link : CVE-2026-6477

CVE.ORG link : CVE-2026-6477

JSON object : View

Products Affected

postgresql

postgresql

CWE

CWE-242

Use of Inherently Dangerous Function

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