What is CVE-2026-6477?

CVE-2026-6477 is a high-severity vulnerability in Postgresql, classified under CWE-242. CVSS score: 8.8/10. Published 2026-05-14.

How severe is CVE-2026-6477?

High severity. CVSS v3 base score is 8.8 out of 10.

Vulnerability in Postgresql

CVE-2026-6477

Use of inherently dangerous function PQfn(..., result_is_int=0, ...) in PostgreSQL libpq lo_export(), lo_read(), lo_lseek64(), and lo_tell64() functions allows the server superuser to overwrite a client stack buffer with an arbitrarily-lar…

EPSS: 0.000 (14.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Postgresql
N/a Postgresql — versions 18, 17, 16

Weakness classification (CWE)

CWE-242

References

f86ef6dc-4d3a-42ad-8f28-e6d5547a5007 (Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-6477?: CVE-2026-6477 is a high-severity vulnerability in Postgresql, classified under CWE-242. CVSS score: 8.8/10. Published 2026-05-14.
How severe is CVE-2026-6477?: High severity. CVSS v3 base score is 8.8 out of 10.