Description
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, a successful POST /login caused is_authorized/2 to set an auth cookie containing base64-encoded username:password credentials without HttpOnly, Secure, SameSite, or expiration protections. Because base64 is encoding rather than encryption, an attacker with same-origin cross-site scripting, an HTTP-readable network position, or local access to the browser cookie store could recover the actual login credentials; older browsers that treated an absent SameSite attribute as None also sent the cookie cross-site. This issue is fixed in versions 4.2.8 and 4.3.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| rabbitmq | rabbitmq-server | >= 4.2.0, < 4.2.8, >= 4.3.0, < 4.3.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rabbitmq-server | 4.3.2-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | rabbitmq-server | 4.0.5-10ubuntu5.2 | USN-8933-1 |
| Ubuntu 24.04 LTS | rabbitmq-server | 3.12.1-1ubuntu1.7 | USN-8933-1 |
| Ubuntu 22.04 LTS | rabbitmq-server | 3.9.27-0ubuntu0.6 | USN-8933-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | rabbitmq-server | 3.8.3-0ubuntu0.3+esm2 | USN-8933-1 |
| Ubuntu Pro 18.04 LTS | rabbitmq-server | 3.6.10-1ubuntu0.5+esm1 | USN-8933-1 |
| Ubuntu Pro 16.04 LTS | rabbitmq-server | 3.5.7-1ubuntu0.16.04.4+esm3 | USN-8933-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | rabbitmq-server4.3 | 4.3.6-1.hum1 | RHSA-2026:67552 |
Advisories 2
- RHSA-2026:67552 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- USN-8933-1 rabbitmq-server vulnerabilities Ubuntu Security Notices (USN) · Nov 3, 2026
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-88vh-gx85-p36m
- https://github.com/rabbitmq/rabbitmq-server/commit/df9e7f4c0afd311a672705f020d301efad355745
- https://github.com/rabbitmq/rabbitmq-server/commit/edf1fbc7217aaf736955d2e13c9534901a2e0778
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.8
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.2