CVE-2026-6475

Summary

Symlink following in PostgreSQL pg_basebackup plain format and in pg_rewind allows an origin superuser to overwrite local files, e.g. /var/lib/postgres/.bashrc, that hijack the operating system account. It will remain the case that starting the server after these commands implicitly trusts the origin superuser, due to features like shared_preload_libraries. Hence, the attack has practical implications only if one takes relevant action between these commands and server start, like moving the files to a different VM or snapshotting the VM. Versions before PostgreSQL 18.4, 17.10, 16.14, 15.18, and 14.23 are affected.

Affected Software

VendorProductVersion RangeStatus
n/aPostgreSQL18 < 18.4affected
n/aPostgreSQL17 < 17.10affected
n/aPostgreSQL16 < 16.14affected
n/aPostgreSQL15 < 15.18affected
n/aPostgreSQL0 < 14.23affected

Weaknesses

  • CWE-61: UNIX Symbolic Link (Symlink) Following

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References