CVE-2026-48773: proxysql vulnerability

What is known

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.

Business impact

Successful exploitation of CVE-2026-48773, a critical vulnerability (CVSS 9.8) affecting proxysql, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether proxysql is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
• Reference
• Reference