Description
Improper enforcement of message integrity in PostgreSQL GSSAPI support allows a user to negotiate GSSAPI contrary to pg_hba.conf rules, via initial direct TLS connection. Despite a pg_hba.conf that appears to require GSSAPI, the connection may exchange data over TLS encryption alone. If the TLS settings are more permissive than the GSS settings, the connection may continue with lesser protection. Within major versions 17-18, minor versions before PostgreSQL 18.6 and 17.11 are affected. Versions before PostgreSQL 17 are unaffected.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | PostgreSQL | 18 – < 18.6, 17 – < 17.11 | 18.6 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | postgresql-18 | 18.6-1 | — |
| Debian 13 | postgresql-17 | 17.11-0+deb13u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | postgresql-18 | 18.6-0ubuntu0.26.04.1 | USN-8653-1 |
| Ubuntu 24.04 LTS | postgresql-16 | 16.15-0ubuntu0.24.04.1 | USN-8653-1 |
| Ubuntu 22.04 LTS | postgresql-14 | 14.24-0ubuntu0.22.04.1 | USN-8653-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | postgresql-9.3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | postgresql17 | 17.11-150600.13.32.1 | SUSE-SU-2026:4016-1 |
| SLES 15 SP7 | postgresql18 | 18.6-150600.13.16.1 | SUSE-SU-2026:4014-1 |
| SLES 15 SP6 | postgresql17 | 17.11-150600.13.32.1 | SUSE-SU-2026:4016-1 |
| SLES 15 SP6 | postgresql18 | 18.6-150600.13.16.1 | SUSE-SU-2026:4014-1 |
| SLES 15 SP5 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLES 15 SP5 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
| SLES 15 SP4 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLES 15 SP4 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
| SLES 12 SP5 | postgresql18 | 18.6-8.17.1 | SUSE-SU-2026:3942-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | postgresql17 | 17.11-160000.1.1 | SUSE-SU-2026:23582-1 |
| SLES for SAP 16.0 | postgresql18 | 18.6-160000.1.1 | SUSE-SU-2026:23577-1 |
| SLES for SAP 15 SP6 | postgresql17 | 17.11-150600.13.32.1 | SUSE-SU-2026:4016-1 |
| SLES for SAP 15 SP6 | postgresql18 | 18.6-150600.13.16.1 | SUSE-SU-2026:4014-1 |
| SLES for SAP 15 SP5 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLES for SAP 15 SP5 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
| SLES for SAP 15 SP4 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLES for SAP 15 SP4 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
| SLES 16.0 | postgresql17 | 17.11-160000.1.1 | SUSE-SU-2026:23582-1 |
| SLES 16.0 | postgresql18 | 18.6-160000.1.1 | SUSE-SU-2026:23577-1 |
| SLE HPC 15 SP5 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLE HPC 15 SP5 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
| SLE HPC 15 SP4 | postgresql17 | 17.11-150200.5.33.1 | SUSE-SU-2026:4013-1 |
| SLE HPC 15 SP4 | postgresql18 | 18.6-150200.5.17.1 | SUSE-SU-2026:4015-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | postgresql17 | 17.11-1.1 | openSUSE-SU-2026:11555-1 |
| openSUSE Tumbleweed | postgresql18 | 18.6-1.1 | openSUSE-SU-2026:11565-1 |
| openSUSE Leap 16.0 | postgresql17 | 17.11-160000.1.1 | openSUSE-SU-2026:21702-1 |
| openSUSE Leap 16.0 | postgresql18 +1 | 18.6-160000.1.1 | openSUSE-SU-2026:21703-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | postgresql17 | 17.11-r0 | — |
| Alpine v3.24 | postgresql18 | 18.5-r0 | — |
| Alpine v3.23 | postgresql17 | 17.11-r0 | — |
| Alpine v3.23 | postgresql18 | 18.5-r0 | — |
| Alpine v3.22 | postgresql15 | 15.19-r0 | — |
| Alpine v3.22 | postgresql17 | 17.11-r0 | — |
| Alpine v3.21 | postgresql15 | 15.19-r0 | — |
| Alpine v3.21 | postgresql17 | 17.11-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | postgresql17 +15 | 17.11-1.amzn2023.0.1 | ALAS2023-2026-2076 |
| Amazon Linux 2023 | postgresql18 +15 | 18.6-1.amzn2023.0.1 | ALAS2023-2026-2079 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | postgresql-17 | 17.11-r0 | — |
| Wolfi rolling | postgresql-18 | 18.6-r0 | — |
Advisories 15
- WID-SEC-2026-2844 PostgreSQL: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 18, 2026
- SUSE-SU-2026:23582-1 Security update for postgresql17 SUSE / openSUSE Security Updates · Sep 29, 2026
- SUSE-SU-2026:23577-1 Security update for postgresql18 SUSE / openSUSE Security Updates · Sep 29, 2026
- SUSE-SU-2026:4015-1 Security update for postgresql18 SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:4016-1 Security update for postgresql17 SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:4013-1 Security update for postgresql17 SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:4014-1 Security update for postgresql18 SUSE / openSUSE Security Updates · Sep 13, 2026
- SUSE-SU-2026:3942-1 Security update for postgresql18 SUSE / openSUSE Security Updates · Sep 10, 2026
- openSUSE-SU-2026:21702-1 Security update for postgresql17 SUSE / openSUSE Security Updates · Aug 31, 2026
- openSUSE-SU-2026:21703-1 Security update for postgresql18 SUSE / openSUSE Security Updates · Aug 31, 2026
- ALAS2023-2026-2076 Important: postgresql17 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 31, 2026
- ALAS2023-2026-2079 Important: postgresql18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 31, 2026
- openSUSE-SU-2026:11565-1 libecpg6-18.6-1.1 on GA media SUSE / openSUSE Security Updates · Aug 22, 2026
- openSUSE-SU-2026:11555-1 postgresql17-17.11-1.1 on GA media SUSE / openSUSE Security Updates · Aug 21, 2026
- USN-8653-1 postgresql-14, postgresql-16, postgresql-18 vulnerabilities Ubuntu Security Notices (USN) · Aug 20, 2026