CVE-2026-67234 — RabbitMQ: Non-RFC-conformant cookie name when clearing the auth-mechanism preference
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, get_auth_mechanism/1 used term_to_binary/1 on the strict_auth_mechanism or preferred_auth_mechani…
Published: 2026-09-25 · CVSS: 2.3 · CVSS 4.0
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, get_auth_mechanism/1 used term_to_binary/1 on the strict_auth_mechanism or preferred_auth_mechanism atom when clearing the corresponding cookie, producing a non-ASCII cookie name that violates RFC 6265 and can prevent the browser from deleting the preference. The issue is not directly exploitable for code execution or data exfiltration; its security relevance is limited to stale authentication-mechanism preferences persisting across logout and login cycles. This issue is fixed in versions 4.2.8 and 4.3.2.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7