5.1

CVE-2026-63336: rabbitmq rabbitmq-java-client Improper Certificate Validation

CVSS: 5.1v4.0MediumAwaiting analysis
AliasesUBUNTU-CVE-2026-63336DEBIAN-CVE-2026-63336CGA-2h2g-wv4v-f2vj
Published 18-08-2026Last modified 18-08-2026
Open JSON

Vulnerability summary

CVE-2026-63336 is a medium (CVSS 5.1) Improper Certificate Validation vulnerability in rabbitmq rabbitmq-java-client. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22.1% of scored vulnerabilities.

Overall risk
20/100
0100
Low · default modelHow is this calculated?
CVSS score
5.1/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.31%
0%100%
Low · +0.12 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-MX55-R6RF-78JW

Timeline

  1. 18-08-2026
    PublishedVulnerability first disclosed.
  2. 18-08-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.31%

Chance of exploitation in the next 30 days

Percentile

22%

Versus all other CVEs

30-day change

+0.12 pp

From 0.18% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.31%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard26 products
  • cassandra-reaper< 5.0.0-r9
  • conductor< 3.32.1-r3
  • conductor-fips< 3.32.1-r1
  • druid< 37.0.0-r54 | < 37.0.0-r56
  • logstash-8.19< 8.19.20-r1
Wolfi9 products
  • cassandra-reaper< 5.0.0-r9
  • druid< 37.0.0-r54 | < 37.0.0-r56
  • logstash-9.3All versions (No fix recorded)
  • logstash-9.3-iamguarded-compatAll versions (No fix recorded)
  • logstash-9.4< 9.4.5-r3
Com.rabbitmq1 product
  • amqp-client< 5.33.0
Debian1 product
  • rabbitmq-java-clientAll versions (No fix recorded)
Rabbitmq1 product
Ubuntu1 product
  • rabbitmq-java-clientAll versions (No fix recorded)

6 vendors · 39 products

References

12 links
Show all 12 references