9.2

CVE-2026-67404: rabbitmq rabbitmq-server Improper Certificate Validation

CVSS: 9.2v4.0CriticalUndergoing analysis
AliasesUBUNTU-CVE-2026-67404DEBIAN-CVE-2026-67404
Published 23-09-2026Last modified 29-09-2026
Open JSON

Vulnerability summary

CVE-2026-67404 is a critical (CVSS 9.2) Improper Certificate Validation vulnerability in rabbitmq rabbitmq-server. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 13.9% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.2/10
010
Critical · v4.0 (CVE.org)
EPSS score
0.24%
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 2 · Related 1
RHSA-2026:67552USN-8933-1

Timeline

  1. 23-09-2026
    PublishedVulnerability first disclosed.
  2. 29-09-2026
    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, When no CA bundle is available, ssl_options/1 falls back to [{verify, verify_none}] with no warning. An attacker in a man-in-the-middle position can forge the JWKS response, which leads the broker to accept arbitrary JWTs. Preconditions include The OAuth2 plugin must be in use with no cacertfile configured and the OS CA bundle empty or unreadable (for example, in a minimal container), and the attacker must hold a network man-in-the-middle position.. 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

0.24%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

24-09-202619-10-2026
EPSS score
0.24%

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) | < 3.5.7-1ubuntu0.16.04.4+esm3 | < 3.6.10-1ubuntu0.5+esm1 | < 3.8.3-0ubuntu0.3+esm2 | < 3.9.27-0ubuntu0.6 | < 3.12.1-1ubuntu1.7 | < 4.0.5-10ubuntu5.2

3 vendors · 3 products

References

6 links