CVE-2026-6478

PostgreSQL discloses MD5-hashed passwords via covert timing channel

MEDIUM

6.5

CVSS Score

Published: May 14, 2026 at 01:00 PM UTC

Updated: August 25, 2026 at 01:40 PM UTC

2 products affected across 2 vendorsPostgreSQLSelf-Service Automation Portal

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Severity

MEDIUM6.5

Exploit prediction

EPSS 0.6%

SSVC

No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

PostgreSQL · PostgreSQL

95%

v < 14.2315 ≤ v < 15.1815.0 ≤ v < 15.1816 ≤ v < 16.1416.0 ≤ v < 16.1417 ≤ v < 17.1017.0 ≤ v < 17.1018 ≤ v < 18.418.0 ≤ v < 18.415 16 17 18

Affected range stops below 14.23, so it looks safe — our inference, not a vendor statement

Affected range stops below 15.18, so it looks safe — our inference, not a vendor statement

Affected range stops below 16.14, so it looks safe — our inference, not a vendor statement

Affected range stops below 17.10, so it looks safe — our inference, not a vendor statement

Affected range stops below 18.4, so it looks safe — our inference, not a vendor statement

Self-Service Automation Portal · Red Hatrpm

60%

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://www.postgresql.org/support/security/CVE-2026-6478/