CVE & CISA-KEV Catalog

CVE-2026-6478

MEDIUM

6.5

CVSS v3

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.

How to fix

Remediation Available

libpqAmazon

Fixed in:0:18.4-1.amzn2023.0.1

Fixed in:0:18.4-1.amzn2023.0.1

libpq-debuginfoAmazon

Fixed in:0:18.4-1.amzn2023.0.1

Fixed in:0:18.4-1.amzn2023.0.1

libpq-debugsourceAmazon

Fixed in:0:18.4-1.amzn2023.0.1

Fixed in:0:18.4-1.amzn2023.0.1

libpq-develAmazon

Fixed in:0:18.4-1.amzn2023.0.1

Fixed in:0:18.4-1.amzn2023.0.1

libpq-devel-debuginfoAmazon

Fixed in:0:18.4-1.amzn2023.0.1

Fixed in:0:18.4-1.amzn2023.0.1

postgresql15Amazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-contribAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-contrib-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-debugsourceAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-docsAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-docs-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-llvmjitAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-llvmjit-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-plperlAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-plperl-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-plpython3Amazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-plpython3-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-pltclAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-pltcl-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-private-develAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-private-libsAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-private-libs-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-serverAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-server-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-server-develAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-server-devel-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-staticAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-testAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

postgresql15-test-debuginfoAmazon

Fixed in:0:15.18-1.amzn2023.0.1

Fixed in:0:15.18-1.amzn2023.0.1

This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Exploit Intelligence

0.56%probability of exploitation in 30 days

45thpercentile

Moderate risk: more likely to be exploited than 45% of all known CVEs.

References

Related Vulnerabilities

Other CWE-385 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2018-10845	Medium	5.9	3.6%	-	Fix
CVE-2018-10844	Medium	5.9	3.6%	-	Fix
CVE-2020-25659	Medium	5.9	2.4%	-	Fix
CVE-2025-9231	Medium	6.5	2.2%	-	Fix
CVE-2020-25657	Medium	5.9	1.7%	-	Fix
CVE-2020-25658	High	7.5	1.7%	-	Fix

Common questions

How do I fix CVE-2026-6478?

Published advisories record a fix for 198 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2026-6478 being actively exploited?

Not that we know of. CVE-2026-6478 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.56% is the estimated probability that it will be exploited in the next 30 days. That is higher than 45% of all scored CVEs.

How severe is CVE-2026-6478?

CVE-2026-6478 has a CVSS v3 base score of 6.5, rated moderate. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-6478 affect?

Published advisories record a fix for libpq (Amazon), libpq-debuginfo (Amazon), libpq-debugsource (Amazon), libpq-devel (Amazon), and 194 more. The list on this page is capped, so there may be more.

Embed a live status badge for CVE-2026-6478

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-08-25.