RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15, 4.0.20, 4.1.11, and 4.2.6, the Web STOMP WebSocket handler enforced neither max_frame_size nor login_timeout before authentication, allowing an unauthenticated client to keep a connection alive with a slow stream of small frames and accumulate unbounded pre-authentication state. The rabbitmq_web_stomp plugin must be enabled, and no authentication is required to reach the vulnerable path. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-7v63-j4gm-p4rh
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6
https://github.com/rabbitmq/rabbitmq-server/commit/c1000ba89052608c01c052d98016403ba6e92222
https://github.com/rabbitmq/rabbitmq-server/commit/8138edae6d2beaafe699a41a754d17420bdc2068
https://github.com/rabbitmq/rabbitmq-server/commit/0b4080fa5d6f797b6331d0ce1db2b4bacd34560e
Published: 2026-09-25
Updated: 2026-10-20
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 6.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00583