CVE-2026-59303 Dynamic destination cache size is not properly bound in Spring Cloud Stream

Low 3.1 Published 27 Aug 2026 Updated 28 Aug 2026

An attacker can cause a denial of service by exploiting an unbounded dynamic destination cache size in Spring Cloud Stream.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2026-59303?

CVE-2026-59303 is a low-severity denial of service vulnerability in Spring Cloud Stream, published on 27 Aug 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

Official description

Dynamic destination cache size is not properly bound in Spring Cloud Stream. Spring Cloud Stream 5.0.0 - 5.0.2 Spring Cloud Stream 4.3.0 - 4.3.3 Spring Cloud Stream 4.2.0 - 4.2.6

Weakness: CWE-770

Which versions are affected by CVE-2026-59303?

It affects 1 product.

Products include Vmware Spring Cloud Stream.

How do I fix CVE-2026-59303?

Upgrade to a fixed version.

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-2026-59303 being exploited?

There is no known exploitation of CVE-2026-59303 in the wild and no public exploit code.

Sources

Also known as GHSA-6h2m-pr57-ggxv.