Buffer overflow in Proxysql

CVE-2026-48773

ProxySQL is a proxy for MySQL and its forks, as well as PostgreSQL. Versions 2.0.18 through 3.0.8 have a pre-authentication heap memory corruption vulnerability in the MySQL and PostgreSQL protocol first-read paths. A remote unauthenticated client can declare an oversized first packet length, and ProxySQL passes that attacker-controlled length directly to `recv()` while writing into a fixed 32 KB input queue. Version 3.0.9 patches the issue.

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: 0.005 (39.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% 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-2026-48773: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-48773?
CVE-2026-48773 is a critical-severity vulnerability in Proxysql, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2026-06-19.
How severe is CVE-2026-48773?
Critical severity. CVSS v3 base score is 9.8 out of 10.