Volcano (scheduler, Elastic service and extender plugin response handling): The scheduler reads unbounded responses

Impact

The scheduler reads unbounded responses from the Elastic service and from extender plugins. Since operators commonly run those in separate pods or on separate nodes, compromising one lets an attacker cross the node isolation boundary and take down the shared Volcano scheduler - which stops GPU job placement for every tenant on the cluster.

Who can reach it

An attacker who has already compromised the Elastic service or an extender plugin process, typically running on a different pod or node than the scheduler.

What to do

Upgrade Volcano to 1.9.1, 1.10.2, 1.11.2, 1.11.0-network-topology-preview.3 or 1.12.0-alpha.2 depending on your track, and restart the scheduler. Also treat extender plugin endpoints as untrusted input and keep them on a restricted network path.

References