CVE-2026-102469 Deserialization in Eclipse Vert.x
A malicious DRDA server can trigger unsafe Java deserialization in the Vert.x DB2 client, potentially leading to remote code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-102469?
CVE-2026-102469 is a critical unsafe deserialization vulnerability in Eclipse Vert.x, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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 DB2 client (vertx-db2-client) contains DRDA protocol handling code that deserializes User Defined Type (UDT) column data using a bare ObjectInputStream.readObject() call with no ObjectInputFilter or class allowlist.
This code path is triggered when a DRDA server sends a result set with a column tagged as UDT (FDOCA protocol LID 0x50). However, DB2 does not support this type of UDT. The FDOCA 0x50 type is never sent by a legitimate DB2 server.
Nevertheless, a malicious or man-in-the-middle DRDA server could craft a response with a 0x50-tagged column, causing the client to deserialize arbitrary attacker-controlled bytes on the Vert.x event loop before any application code can inspect or reject the data. If a Java deserialization gadget chain is present on the application's classpath, this enables remote code execution. Without a gadget chain, denial of service is possible via crafted object graphs. TLS is disabled by default, making man-in-the-middle exploitation feasible.
The impacted component is io.vertx:vertx-db2-client.
Weakness: CWE-502
Which versions are affected by CVE-2026-102469?
It affects 1 product.
Products include Eclipse Vert.x.
How do I fix CVE-2026-102469?
No fix has been published for CVE-2026-102469 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-102469 being exploited?
There is no known exploitation of CVE-2026-102469 in the wild and no public exploit code.
Other vulnerabilities in Eclipse Vert.x
- CVE-2019-17640 Path Traversal in Eclipse Vert
- CVE-2018-12542 Eclipse Vert.x does not properly neutralize '' (forward slashes) sequences that can resolve to an external location
- CVE-2018-12544 Moderate severity vulnerability that affects io.vertx:vertx-core
- CVE-2018-12540 High severity vulnerability that affects io.vertx:vertx-web
- CVE-2026-102461 Denial of service in Eclipse Vert.x
Sources
Also known as GHSA-j4vf-w939-pgxf, GHSA-mxgf-c753-mmc9.