Integer overflow in PostgreSQL

CVE-2025-12818

Integer wraparound in multiple PostgreSQL libpq client library functions allows an application input provider or network peer to cause libpq to undersize an allocation and write out-of-bounds by hundreds of megabytes. This results in a segmentation fault for the application using libpq. Versions before PostgreSQL 18.1, 17.7, 16.11, 15.15, 14.20, and 13.23 are affected.

Vulnerability class: Integer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.003 (24.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-12818: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

  • PostgreSQL — versions 18, 17, 16

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-12818?
CVE-2025-12818 is a medium-severity vulnerability in PostgreSQL, classified under Integer Overflow or Wraparound. CVSS score: 5.9/10. Published 2025-11-13.
How severe is CVE-2025-12818?
Medium severity. CVSS v3 base score is 5.9 out of 10.