CVE-2026-63252 Denial of service in Eclipse Milo

High 8.7 Published 4 Aug 2026 Updated 4 Aug 2026

Remote unauthenticated attackers can exhaust server memory by sending incomplete chunks, causing denial of service in Eclipse Milo OPC UA servers.

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-2026-63252?

CVE-2026-63252 is a high-severity denial of service vulnerability in Eclipse Milo, published on 4 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Eclipse Milo versions 0.6.0 through 1.1.4, UASC server transport handlers fail to release retained partial message chunks when a channel disconnects, allowing a remote unauthenticated client to exhaust pooled direct memory by repeatedly sending incomplete chunks and disconnecting, potentially terminating the server.

Weakness: CWE-401

Which versions are affected by CVE-2026-63252?

It affects 1 product.

Products include Eclipse Milo.

How do I fix CVE-2026-63252?

No fix has been published for CVE-2026-63252 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-2026-63252 being exploited?

There is no known exploitation of CVE-2026-63252 in the wild and no public exploit code.

Sources

Also known as GHSA-8mrr-fgjx-37mf.