CVE-2026-102477 Denial of service in Eclipse Vert.x

High 8.7 Published 15 Oct 2026 Updated 15 Oct 2026

Attackers can cause denial of service in Eclipse Vert.x gRPC endpoints by sending compressed messages that expand beyond configured size limits.

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-2026-102477?

CVE-2026-102477 is a high-severity denial of service 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], a gRPC endpoint does have a configurable per message maximum size in bytes, however the maximum size applies to the received bytes. When applied to a compressed message, this only applies to the compressed size and not the actual size of the uncompressed content. This can be used to force a gRPC endpoint to allocate more bytes than the value defined by the configuration, making the endpoint vulnerable to compression bomb attacks.

The impacted component is io.vertx:vertx-gprc-server.

Weakness: CWE-409

Which versions are affected by CVE-2026-102477?

It affects 1 product.

Products include Eclipse Vert.x.

How do I fix CVE-2026-102477?

No fix has been published for CVE-2026-102477 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-102477 being exploited?

There is no known exploitation of CVE-2026-102477 in the wild and no public exploit code.

Sources

Also known as GHSA-3f8m-f8fw-9m74, GHSA-4wvq-75mw-q6cg.