Uncontrolled recursion in PostgreSQL SSL and GSS negotiation allows an attacker able to connect to a PostgreSQL AF_UNIX socket to achieve sustained denial of service. If SSL and GSS are both disabled, an attacker can do the same via access to a PostgreSQL TCP socket. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.
The PostgreSQL project thanks Calif.io in collaboration with Claude and Anthropic Research for reporting this problem.
| Affected Version | Fixed In | Fix Published |
|---|---|---|
| 18 | 18.4 | 2026-05-12 |
| 17 | 17.10 | 2026-05-12 |
| 16 | 16.14 | 2026-05-12 |
| 15 | 15.18 | 2026-05-12 |
| 14 | 14.23 | 2026-05-12 |
For more information about PostgreSQL versioning, please visit the versioning page.
| Overall Score | 7.5 |
|---|---|
| Component | core server |
| Vector | AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
If you wish to report a new security vulnerability in PostgreSQL, please send an email to security@postgresql.org.
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