CVE-2026-6478

Covert timing channel in comparison of MD5-hashed password in PostgreSQL authentication allows an attacker to recover user credentials sufficient to authenticate. This does not affect scram-sha-256 passwords, the default in all supported releases. However, current databases may have MD5-hashed passwords originating in upgrades from PostgreSQL 13 or earlier. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.postgresql.org/support/security/CVE-2026-6478/	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
First Time		Postgresql Postgresql postgresql
References	~~() https://www.postgresql.org/support/security/CVE-2026-6478/ -~~	() https://www.postgresql.org/support/security/CVE-2026-6478/ - Patch, Vendor Advisory
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-2026-6478

Mitre link : CVE-2026-6478

CVE.ORG link : CVE-2026-6478

JSON object : View

Products Affected

postgresql

postgresql

CWE

CWE-385

Covert Timing Channel

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