5.3

CVE-2026-67405: rabbitmq rabbitmq-server Missing Origin Validation in WebSockets

CVSS: 5.3v4.0MediumUndergoing analysis
AliasesUBUNTU-CVE-2026-67405DEBIAN-CVE-2026-67405
Published 23-09-2026Last modified 24-09-2026
Open JSON

Vulnerability summary

CVE-2026-67405 is a medium (CVSS 5.3) Missing Origin Validation in WebSockets vulnerability in rabbitmq rabbitmq-server. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.13%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1
RHSA-2026:67552

Timeline

  1. 23-09-2026
    PublishedVulnerability first disclosed.
  2. 24-09-2026
    Last modifiedVulnerability information updated.

Description

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, Neither the Web-MQTT handler (deps/rabbitmq_web_mqtt/src/rabbit_web_mqtt_handler.erl:104) nor the Web-STOMP handler (deps/rabbitmq_web_stomp/src/rabbit_web_stomp_handler.erl:102) validates the Origin header on the WebSocket upgrade. Under ssl_cert_login=true, the browser presents the client certificate automatically, so an attacker's JavaScript running in the victim's browser can authenticate as the victim. Preconditions include The non-default configuration use_http_auth=true (Web-STOMP) or ssl_cert_login=true (both plugins) must be enabled. The issue is harmless under the default in-band CONNECT credential configuration.. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

24-09-202619-10-2026
EPSS score
0.13%

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

Debian1 product
  • rabbitmq-serverAll versions (No fix recorded) | < 4.3.0-2
Rabbitmq1 product
  • rabbitmq-server≥ 3.13.0, < 3.13.15 | ≥ 4.0.0, < 4.0.20 | ≥ 4.1.0, < 4.1.11 | ≥ 4.2.0, < 4.2.6
Ubuntu1 product
  • rabbitmq-serverAll versions (No fix recorded)

3 vendors · 3 products

References

6 links