Buffer overflow in Github.com/jackc/pgx/v5 Github.com/jackc/pgx/v5/pgproto3

CVE-2026-33816

Memory-safety vulnerability in github.com/jackc/pgx/v5.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (56.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.9% 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-2026-33816: held from 0.006 to 0.009.

EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33816?
CVE-2026-33816 is a critical-severity vulnerability in Github.com/jackc/pgx/v5 Github.com/jackc/pgx/v5/pgproto3, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-04-07.
How severe is CVE-2026-33816?
Critical severity. CVSS v3 base score is 9.8 out of 10.