Is CVE-2026-102476 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102476 being exploited in the wild.

How severe is CVE-2026-102476?

Informational severity, published 14 October 2026.

Which products and versions are affected?

Eclipse Vert.X 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0.

Is there a fix for CVE-2026-102476?

Yes: fixed in 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-2026-102476 attacked?

It is attacked over the network.

Am I affected by CVE-2026-102476?

Check whether you run Eclipse Vert.X 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-2026-102476: Eclipse Vert.x HTTP client SSL context cache key insufficiency

CVE-2026-102476 · Severity: info · Published 2026-10-14

Eclipse Vert.x is a Java framework for building reactive applications. Its HTTP client caches SSL connections for efficiency, but the cache key does not fully account for all security properties (such as hostname validation requirements), allowing an attacker to obtain a reused SSL connection with weaker security settings than requested. This could enable man-in-the-middle attacks against applications using the HTTP client.

Technologies: Eclipse Vert.X. Vendors: Eclipse.

Quick answers

Is CVE-2026-102476 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102476 being exploited in the wild.
How severe is CVE-2026-102476?: Informational severity, published 14 October 2026.
Which products and versions are affected?: Eclipse Vert.X 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0.
Is there a fix for CVE-2026-102476?: Yes: fixed in 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-2026-102476 attacked?: It is attacked over the network.
Am I affected by CVE-2026-102476?: Check whether you run Eclipse Vert.X 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: 5.1.10, 5.2.1

Technical details

The Vert.x HTTP client's SSL context caching mechanism uses an incomplete cache key that fails to incorporate all SSL semantics, allowing a connection request with one set of SSL properties to match and reuse a cached context with different (weaker) properties. For example, a request for hostname validation could receive a cached context without hostname validation. An attacker with network position can exploit this to intercept connections when a client reuses a previously cached SSL context with insufficient security properties.

Affected products

Eclipse Vert.x 5.0.0 to 5.0.12, 5.1.0 to 5.1.9, 5.2.0

Timeline

2026-10-07: advisory
2026-10-14: disclosed

References

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