CVE-2026-6475: PostgreSQL symlink following in pg_basebackup and pg_rewind

CVE-2026-6475 · Severity: high · CVSS 8.8 · Published 2026-05-14

PostgreSQL database backup and synchronization tools contain a flaw that allows a malicious database administrator to overwrite sensitive files on the system performing the backup. This could allow an attacker to gain full control over the underlying operating system account by modifying configuration files like .bashrc. The risk is highest when backup files are moved between systems or snapshotted before the database server is restarted.

Technologies: PostgreSQL. Vendors: PostgreSQL.

Quick answers

Is CVE-2026-6475 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-6475 being exploited in the wild.
How severe is CVE-2026-6475?
High severity, with a CVSS score of 8.8, published 14 May 2026.
Which products and versions are affected?
PostgreSQL < 18.4, < 17.10, < 16.14, < 15.18, < 14.23.
Is there a fix for CVE-2026-6475?
A patch was published on 2026-05-12: Fixes released for supported versions. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-6475 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-6475?
Check whether you run PostgreSQL at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A symbolic link (symlink) following vulnerability exists in the PostgreSQL client tools pg_basebackup (when using plain format) and pg_rewind. A database superuser on the source (origin) server can craft malicious symlinks that cause these tools to overwrite arbitrary files on the local filesystem where the tools are being executed. This can lead to privilege escalation or account takeover by overwriting sensitive files such as .bashrc. The vulnerability is particularly relevant in scenarios where the backup files are manipulated (e.g., moved to a different VM or snapshotted) before the database server is started. Patches are available in PostgreSQL versions 18.4, 17.10, 16.14, 15.18, and 14.23.

Affected products

  • PostgreSQL PostgreSQL < 18.4, < 17.10, < 16.14, < 15.18, < 14.23

Timeline

  • 2026-05-12: patched: Fixes released for supported versions.
  • 2026-05-14: disclosed: Public advisory published.

References

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