CVE-2026-6478: PostgreSQL · Covert Timing Channel
Affects PostgreSQLSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium · fixed in 18.4 : update PostgreSQL when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 18.4, 17.10, 16.14 +2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 14 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PostgreSQL | Affected
| Fixed in
|
| PostgreSQL | Affected
| Fixed in
|
| PostgreSQL | Affected
| Fixed in
|
| PostgreSQL | Affected
| Fixed in
|
| PostgreSQL | Affected
| Fixed in
|
Postgresqlpostgresql/postgresqlpkg:deb/postgresql/postgresqlOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available and has been released in PostgreSQL versions 14.23, 15.18, 16.14, 17.10, and 18.4 and later, as provided by Red Hat security advisories. Users should upgrade to these fixed versions. Additionally, to mitigate the vulnerability, users must ensure that no PostgreSQL user passwords are hashed using MD5. This can be done by altering user passwords to trigger migration to stronger hashing algorithms such as scram-sha-256. For example, execute: ALTER USER username WITH PASSWORD 'new_password'; This requires users to re-authenticate, and services relying on these credentials may need to be restarted to pick up the changes. No other mitigations are indicated by the vendor advisory.
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.
References
- postgresql.org/support/security/CVE-2026-6478/ (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-6478 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2477447 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6478.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27718 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27743 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27742 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27738 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28999 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28208 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26181 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28143 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:44420 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34362 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34363 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:29815 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:32994 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:35880 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34043 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:42555 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26561 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:33497 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:29953 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:33441 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26524 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:29904 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:32983 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26525 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:29212 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28037 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26203 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26204 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27741 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:21182 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:22878 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:44481 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:49521 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:58981 (opens in a new tab)