Is CVE-2026-67234 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-67234 being exploited in the wild.

How severe is CVE-2026-67234?

Informational severity, published 25 September 2026.

Which products and versions are affected?

RabbitMQ 4.2.0 to 4.2.7, 4.3.0 to 4.3.1.

Is there a fix for CVE-2026-67234?

A patch was published on 2026-09-25: Fixed in RabbitMQ 4.2.8 and 4.3.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-67234 attacked?

It is attacked over the network.

Am I affected by CVE-2026-67234?

Check whether you run RabbitMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-67234: RabbitMQ non-RFC-conformant cookie name in auth mechanism

CVE-2026-67234 · Severity: info · Published 2026-09-25

RabbitMQ, a message broker used in enterprise messaging systems, generates RFC 6265-noncompliant cookie names when clearing authentication preferences. This prevents browsers from properly deleting preference cookies, allowing stale authentication mechanism choices to persist across user logout and login cycles, potentially exposing preferences.

Technologies: RabbitMQ. Vendors: RabbitMQ.

Quick answers

Is CVE-2026-67234 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-67234 being exploited in the wild.
How severe is CVE-2026-67234?: Informational severity, published 25 September 2026.
Which products and versions are affected?: RabbitMQ 4.2.0 to 4.2.7, 4.3.0 to 4.3.1.
Is there a fix for CVE-2026-67234?: A patch was published on 2026-09-25: Fixed in RabbitMQ 4.2.8 and 4.3.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-67234 attacked?: It is attacked over the network.
Am I affected by CVE-2026-67234?: Check whether you run RabbitMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The get_auth_mechanism/1 function in rabbit_mgmt_oauth_bootstrap.erl incorrectly used term_to_binary/1 to generate cookie names for clearing auth preferences, producing non-ASCII binary data that violates RFC 6265 cookie naming standards. This causes browsers to ignore the cookie deletion requests, leaving stale authentication mechanism preferences in storage. The fix replaces term_to_binary/1 with atom_to_binary/1 to generate RFC-compliant cookie names.

Affected products

RabbitMQ RabbitMQ 4.2.0 to 4.2.7, 4.3.0 to 4.3.1

Timeline

2026-09-25: disclosed
2026-09-25: patched: Fixed in RabbitMQ 4.2.8 and 4.3.2

References

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