5.1
MEDIUM CVSS 4.0
CVE-2026-63336
RabbitMQ Java client: TrustEverythingTrustManager used by default in useSslProtocol() enables MITM
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.client.ConnectionFactory.useSslProtocol() and ConnectionFactory.useSslProtocol(String) configure com.rabbitmq.client.TrustEverythingTrustManager and leave hostname verification disabled, causing arbitrary server certificates, including self-signed certificates, to be accepted. A network attacker able to intercept a TLS connection can impersonate the RabbitMQ broker, read protected AMQP traffic, and modify traffic without certificate or hostname validation. The fix changes the production TLS helpers to use the JVM default trust store and enables hostname verification, while retaining an explicitly named development-only no-verification helper. This issue is fixed in version 5.33.0.

INFO

Published Date :

Aug. 18, 2026, 5:17 p.m.

Last Modified :

Aug. 18, 2026, 6:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-63336 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 4.0 MEDIUM [email protected]
Solution
Update RabbitMQ Java client to 5.33.0 to enable TLS hostname verification.
  • Update the RabbitMQ Java client library to version 5.33.0 or later.
  • Ensure TLS hostname verification is enabled in the connection factory.
  • Use the production TLS helpers for secure connections.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63336 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-63336 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-63336 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63336 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 18, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-5m9f-rphj-c435
    Added SSVC {'id': 'CVE-2026-63336', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-18T17:30:07.570827Z'}
  • New CVE Received by [email protected]

    Aug. 18, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'rabbitmq', 'product': 'rabbitmq-java-client', 'versions': [{'status': 'affected', 'version': '< 5.33.0'}]}]
    Added 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.client.ConnectionFactory.useSslProtocol() and ConnectionFactory.useSslProtocol(String) configure com.rabbitmq.client.TrustEverythingTrustManager and leave hostname verification disabled, causing arbitrary server certificates, including self-signed certificates, to be accepted. A network attacker able to intercept a TLS connection can impersonate the RabbitMQ broker, read protected AMQP traffic, and modify traffic without certificate or hostname validation. The fix changes the production TLS helpers to use the JVM default trust store and enables hostname verification, while retaining an explicitly named development-only no-verification helper. This issue is fixed in version 5.33.0.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-295
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/commit/1e7deb2e6020c9793a81385a53ea378ec63b9339
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/commit/a4bf571dd368765baaa9cecfae68ce09f1bdcc01
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/pull/1999
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/pull/2001
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.33.0
    Added Reference https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-5m9f-rphj-c435
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.