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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63337 Detail

Description

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.33.0, com.rabbitmq.tools.jsonrpc.ProcedureDescription receives a javaReturnType value in an untrusted system.describe response and passes it through JSONUtil.tryFill, setJavaReturnType, and computeReturnTypeAsJavaClass to Class.forName(javaReturnType) with initialization enabled. An attacker able to answer the JsonRpcClient request through a shared broker or network interception can select a class already present in the victim JVM and trigger its static initializer, while JsonRpcClient.java later passes getReturnType output to mapper.parse and may also create type confusion. Successful exploitation can affect confidentiality, integrity, and availability in the client process. This issue is fixed in version 5.33.0.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 7.5 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/rabbitmq/rabbitmq-java-client/commit/0032f75f9dc3df847f94b2b85a16119250bf63cb GitHub, Inc.
https://github.com/rabbitmq/rabbitmq-java-client/commit/9f8e7efd0c648f235dc0e96232ae7efa75ea4fa8 GitHub, Inc.
https://github.com/rabbitmq/rabbitmq-java-client/pull/2000 GitHub, Inc.
https://github.com/rabbitmq/rabbitmq-java-client/pull/2002 GitHub, Inc.
https://github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.33.0 GitHub, Inc.
https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-6g32-pxv4-2wfj GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-470 Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63337
NVD Published Date:
08/18/2026
NVD Last Modified:
08/18/2026
Source:
GitHub, Inc.