CVE-2026-112269: SGLang through 0.5.22 Memory Exhaustion via Unauthenticated Mooncake Decode Registrations
SGLang through 0.5.22 with the Mooncake disaggregation backend accepts unauthenticated decode registration messages on the Prefill rank ZMQ PULL socket, allowing denial of service. Network-adjacent attackers can send many registrations with unique mooncakesessionid values and large nested-buffer frames to exhaust Prefill memory until the scheduler is OOM-killed.
Affected Software
Event History
Frequently Asked Questions
Which deployments are exposed?
SGLang deployments through 0.5.22 that use the Mooncake disaggregation backend are exposed when an attacker can reach the Prefill rank ZMQ PULL socket over an adjacent network.
What does an attacker need to exploit this issue?
No authentication or user interaction is required. An attacker needs network access to send decode registration messages to the Prefill rank socket, using many unique mooncake_session_id values and large nested-buffer frames.
What is the operational impact?
The registrations can exhaust memory on the Prefill process until the scheduler is killed by an out-of-memory condition, causing denial of service.
What can be done if patching is not immediately possible?
Restrict network access to the Prefill rank ZMQ PULL socket so untrusted adjacent-network systems cannot send decode registration messages.