Threat Intelligence Database

CVE-2026-103224 is a high-severity vulnerability in Eclipse Vert.x's MySQL client component. It affects versions 4.0.0 through 4.5.34, 5.0.0 through 5.0.12, 5.1.0 through 5.1.9, and version 5.2.0. The flaw involves the MySQL message decoder aggregating inbound multi-packet payloads into a direct-memory buffer without a size limit, allowing a malicious or compromised MySQL server to cause unbounded memory allocation and an out-of-memory crash before authentication completes.

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 Vert.x MySQL client (vertx-mysql-client) pre-allocates an array for column definitions based on a server-declared column count with no upper-bound validation. A malicious or compromised MySQL server, or an attacker with man-in-the-middle positioning, can send a crafted result set packet with an extremely large column count, causing the client to attempt a massive heap allocation. The resulting OutOfMemoryError crashes the Netty event loop thread, causing a complete denial of service for all connections and verticles in the Vert.x application. The impacted component is io.vertx:vertx-mysql-client.