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.
Weakness
The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Vert.x | Eclipse | 4.5.0 (including) | 4.5.35 (excluding) |
| Vert.x | Eclipse | 5.0.0 (including) | 5.1.10 (excluding) |
| Vert.x | Eclipse | 5.2.0 (including) | 5.2.0 (including) |