Is CVE-2026-102466 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102466 being exploited in the wild.

How severe is CVE-2026-102466?

Medium severity, with a CVSS score of 5.9, published 15 October 2026.

Which products and versions are affected?

Eclipse Vert.x MySQL client 4.0.0 to 4.5.34, 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0.

Is there a fix for CVE-2026-102466?

Yes: fixed in 4.5.35, 5.1.10, 5.2.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-102466 attacked?

It is attacked over the network.

Am I affected by CVE-2026-102466?

Check whether you run Eclipse Vert.X or Eclipse Vert.x MySQL client at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-102466: Eclipse Vert.x MySQL client denial of service via uncapped column count

CVE-2026-102466 · Severity: medium · CVSS 5.9 · Published 2026-10-15

Eclipse Vert.x is a toolkit for building reactive Java applications that connect to databases like MySQL. The MySQL client component fails to validate column count values received from a database server, allowing a malicious or compromised server—or an attacker positioned between the application and server—to send a crafted response that triggers a massive memory allocation. This causes the application to crash, making it unavailable to all users.

Technologies: Eclipse Vert.X. Vendors: Eclipse.

Quick answers

Is CVE-2026-102466 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102466 being exploited in the wild.
How severe is CVE-2026-102466?: Medium severity, with a CVSS score of 5.9, published 15 October 2026.
Which products and versions are affected?: Eclipse Vert.x MySQL client 4.0.0 to 4.5.34, 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0.
Is there a fix for CVE-2026-102466?: Yes: fixed in 4.5.35, 5.1.10, 5.2.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-102466 attacked?: It is attacked over the network.
Am I affected by CVE-2026-102466?: Check whether you run Eclipse Vert.X or Eclipse Vert.x MySQL client at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 4.5.35, 5.1.10, 5.2.1

Technical details

The vertx-mysql-client pre-allocates a column definitions array based on a server-declared column count without upper-bound validation. An attacker controlling or intercepting the MySQL connection can send a result set packet with an extremely large column count, causing an OutOfMemoryError that crashes the Netty event loop thread and denies service to all connections in the Vert.x application. The vulnerability requires network access to the MySQL connection or a man-in-the-middle position.

Affected products

Eclipse Vert.x MySQL client 4.0.0 to 4.5.34, 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0

Timeline

2026-10-07: disclosed
2026-10-15: advisory

References

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