CVE-2026-103224: Maven/io.vertx/vertx-mysql-client vulnerability
In Eclipse Vert.x versions [4.0.0, 4.5.34] or [5.0.0,5.0.12] or [5.1.0,5.1.9] or [5.2.0, 5.2.0], the MySQL message decoder aggregates inbound multi-packet payloads into a composite direct-memory buffer without any cumulative size limit. A malicious, compromised, or man-in-the-middle MySQL server can send a continuous stream of packets with the maximum payload length (0xFFFFFF), preventing the end-of-message condition from being reached, causing unbounded direct-memory allocation on the client and leading to an out-of-memory crash. This occurs before authentication completes.
The impacted component is io.vertx:vertx-mysql-client.
Affected Software
Event History
Frequently Asked Questions
Which deployments should be prioritized for remediation?
Prioritize applications that use io.vertx:vertx-mysql-client in the affected versions and connect to MySQL servers that could be malicious, compromised, or subject to a man-in-the-middle attacker. The affected behavior is in the client-side MySQL message decoder.
Does an attacker need valid MySQL credentials to trigger the issue?
No. The condition occurs before authentication completes, so a malicious server or an attacker able to impersonate or intercept the server connection can trigger it without completing MySQL authentication.