# CVE-2026-75516: RabbitMQ Java client: Frame-level OOM: Math.min(maxInboundMessageBodySize, 0) defeats frame size enforcement

> A malicious server or MITM attacker can cause client memory exhaustion and process termination by exploiting a frame size validation flaw in the RabbitMQ Java client.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Sep 2026
- **Updated:** 18 Sep 2026
- **Also known as:** CLEANSTART-2026-FQ92351, CLEANSTART-2026-UX42229, CLEANSTART-2026-YJ89488, DEBIAN-CVE-2026-75516, ECHO-c374-3c74-70ef, GHSA-jh4v-gfqj-7rhx, MINI-22rv-ggc7-v585, MINI-3hcp-65rg-pcpf, MINI-58mq-q6vj-cx26, MINI-5h6w-q4cq-vfgj, MINI-5pqq-v769-cch4, MINI-5x2x-wjcx-rmj9, MINI-5xrv-3846-284f, MINI-64hh-hqv6-3jxj, MINI-mmqm-6q5j-fqpj, MINI-qm4h-x87q-wmcr, MINI-rc9m-wgg5-33mp, MINI-rv4v-g344-mggq, MINI-vwrw-h5vm-22fp, MINI-wh8x-99rh-r8xv, ROOT-APP-MAVEN-CVE-2026-75516, UBUNTU-CVE-2026-75516

## What is CVE-2026-75516?

CVE-2026-75516 is a high-severity denial of service vulnerability in rabbitmq-java-client, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.34.0, AMQConnection.start() applies Math.min(maxInboundMessageBodySize, frameMax) after Connection.Tune negotiation even though AMQP defines frameMax value zero as unlimited and ConnectionFactory.DEFAULT_FRAME_MAX is zero. When the client default and server-negotiated value are both zero, the result is passed to Utils.framePayloadLimit(int), which interprets zero as Integer.MAX_VALUE and disables the configured maxInboundMessageBodySize cap. A malicious AMQP server, or a man-in-the-middle attacker able to modify Connection.Tune and inject frames into the connection, can then send an oversized frame of any frame type, causing Frame.readFrom() to allocate a large byte array before content-level validation and potentially terminate the client process through memory exhaustion. This issue is fixed in version 5.34.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-75516?

2 open source packages ship an affected version, including com.rabbitmq:amqp-client.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `com.rabbitmq:amqp-client` | Maven | All versions | 5.34.0 |
| `com.rabbitmq:amqp-client` | Maven | All versions | 5.34.0 |

## How do I fix CVE-2026-75516?

Upgrade com.rabbitmq:amqp-client to 5.34.0 or later.

## Is CVE-2026-75516 being exploited?

There is no known exploitation of CVE-2026-75516 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75516 and fix it if it is affected.

What it is: CVE-2026-75516 is a high-severity denial of service vulnerability in rabbitmq-java-client, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-75516 in the wild and no public exploit code.

Affected packages and fixed versions:
- com.rabbitmq:amqp-client (Maven): affected all versions; fixed in 5.34.0
- com.rabbitmq:amqp-client (Maven): affected all versions; fixed in 5.34.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-75516/ (Markdown: https://insights.sbomify.com/CVE-2026-75516/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75516
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75516
- OSV: https://osv.dev/vulnerability/CVE-2026-75516

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75516/
Summaries are generated and may contain mistakes; the official description above is the record.