# RHSA-2026:27742: postgresql18 security update

RHSA-2026:27742, released May 14, 2026, fixes 10 CVEs in postgresql18 (version 18.4-1.el10_2). None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2026-27742
- Platform: Linux
- Released: May 14, 2026
- Priority: High (Closes CVE-2026-6473, high severity)
- CVEs: 10, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2026:27742

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [postgresql18](https://patchblox.com/security/data/product/linux/postgresql18.md) | RHEL 10 | 18.4-1.el10_2 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2026-6473](https://patchblox.com/security/data/cve/CVE-2026-6473.md) | High | PostgreSQL server undersizes allocations, via integer wraparound | 8.8 | 0.0101 |  |
| [CVE-2026-6479](https://patchblox.com/security/data/cve/CVE-2026-6479.md) | High | PostgreSQL SSL/GSS init causes denial of service, via uncontrolled recursion | 7.5 | 0.0060 |  |
| [CVE-2026-6478](https://patchblox.com/security/data/cve/CVE-2026-6478.md) | High | PostgreSQL discloses MD5-hashed passwords via covert timing channel | 8.8 | 0.0056 |  |
| [CVE-2026-6477](https://patchblox.com/security/data/cve/CVE-2026-6477.md) | High | PostgreSQL libpq lo_* functions let server superuser overwrite client stack memory | 8.8 | 0.0045 |  |
| [CVE-2026-6475](https://patchblox.com/security/data/cve/CVE-2026-6475.md) | High | PostgreSQL pg_basebackup and pg_rewind can overwrite unrelated files of origin superuser choice | 8.8 | 0.0041 |  |
| [CVE-2026-6637](https://patchblox.com/security/data/cve/CVE-2026-6637.md) | High | PostgreSQL refint allows stack buffer overflow and SQL injection | 8.8 | 0.0037 |  |
| [CVE-2026-6638](https://patchblox.com/security/data/cve/CVE-2026-6638.md) | High | PostgreSQL REFRESH PUBLICATION allows SQL injection via table name | 8.8 | 0.0018 |  |
| [CVE-2026-6474](https://patchblox.com/security/data/cve/CVE-2026-6474.md) | Routine | PostgreSQL timeofday() can disclose portions of server memory | 4.3 | 0.0021 |  |
| [CVE-2026-6575](https://patchblox.com/security/data/cve/CVE-2026-6575.md) | Routine | pgaudit: PostgreSQL is an advanced object-relational database management system (DBMS) | 4.3 | 0.0021 |  |
| [CVE-2026-6472](https://patchblox.com/security/data/cve/CVE-2026-6472.md) | Routine | PostgreSQL CREATE TYPE does not check multirange schema CREATE privilege | 5.4 | 0.0016 |  |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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