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 products
postgresql: postgresql
References10
- www.postgresql.org/support/security/CVE-2026-6478/ PatchVendor Advisory
- access.redhat.com/errata/RHSA-2026:21182
- access.redhat.com/errata/RHSA-2026:22878
- access.redhat.com/errata/RHSA-2026:26181
- access.redhat.com/errata/RHSA-2026:26203
- access.redhat.com/errata/RHSA-2026:26204
- access.redhat.com/errata/RHSA-2026:26524
- access.redhat.com/errata/RHSA-2026:26525
- access.redhat.com/errata/RHSA-2026:26561
- access.redhat.com/errata/RHSA-2026:27718
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 1% percentile: 47 · as of 14 November 2026
- CWE
- CWE-385
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