Red Hat Undertow 2.3.0 Alpha 1

A flaw was found in Undertow. Denial of service can be achieved as Undertow server waits for the LAST_CHUNK forever for EJB invocations.

Published: 2022-09-01T00:00:00.000Z
Updated: 2024-08-03T00:46:04.429Z

When a POST request comes through AJP and the request exceeds the max-post-size limit (maxEntitySize), Undertow's AjpServerRequestConduit implementation closes a connection without sending any response to the client/proxy. This behavior results in that a front-end proxy marking the backend worker (application server) as an error state and not forward requests to the worker for a while. In mod_cluster, this continues until the next STATUS request (10 seconds intervals) from the application server updates the server state. So, in the worst case, it can result in "All workers are in error state" and mod_cluster responds "503 Service Unavailable" for a while (up to 10 seconds). In mod_proxy_balancer, it does not forward requests to the worker until the "retry" timeout passes. However, luckily, mod_proxy_balancer has "forcerecovery" setting (On by default; this parameter can force the immediate recovery of all workers without considering the retry parameter of the workers if all workers of a balancer are in error state.). So, unlike mod_cluster, mod_proxy_balancer does not result in responding "503 Service Unavailable". An attacker could use this behavior to send a malicious request and trigger server errors, resulting in DoS (denial of service). This flaw was fixed in Undertow 2.2.19.Final, Undertow 2.3.0.Alpha2.

Published: 2022-08-05T15:24:27.000Z
Updated: 2024-08-03T00:24:44.066Z

A flaw was found in Undertow. For an AJP 400 response, EAP 7 is improperly sending two response packets, and those packets have the reuse flag set even though JBoss EAP closes the connection. A failure occurs when the connection is reused after a 400 by CPING since it reads in the second SEND_HEADERS response packet instead of a CPONG.

Published: 2022-08-31T00:00:00.000Z
Updated: 2024-08-03T00:03:05.119Z