CVE-2014-3619

What it actually does

Remote attacker can send a crafted 00000000 fragment header that triggers an infinite loop inside the __socket_proto_state_machine function, consuming CPU and preventing further request processing.

Why it matters to the business

GlusterFS storage nodes become unresponsive, causing file-service outages and potential data-access disruption for any dependent applications until the affected process is restarted.

How an attack unfolds

An unauthenticated attacker sends a single specially crafted network fragment containing the 00000000 header to a GlusterFS server; the state machine enters an infinite loop and stops servicing legitimate clients.

How to fix it

Upgrade GlusterFS to a release that resolves the infinite-loop condition in __socket_proto_state_machine; if no fixed package is available, isolate or firewall the service until an update can be applied.

How to confirm the fix worked

Confirm GlusterFS version is newer than 3.5 and test that a 00000000 fragment no longer produces an infinite loop; monitor CPU and request-handling behavior under crafted traffic.

Typical attack path

1. Locate exposed GlusterFS TCP ports
2. Craft and transmit a fragment header containing 00000000
3. Trigger infinite loop in the protocol state machine
4. Observe sustained high CPU and loss of service

How to detect it

Review GlusterFS process logs and system logs for repeated state-machine entries or sustained high CPU on the glusterfsd process; inspect network captures for fragments carrying the literal 00000000 header.

• 00000000 fragment header in GlusterFS protocol traffic
• sustained high CPU utilization on glusterfsd process
• repeated __socket_proto_state_machine log entries without progress

What your security team should do

• Apply the latest GlusterFS package as soon as it becomes available
• Restrict network access to GlusterFS ports to trusted clients only
• Add network-level filtering to drop fragments containing the 00000000 header pattern
• Monitor process CPU usage for sudden sustained spikes on GlusterFS nodes