CVE-2026-106041 in Mooncake
Summary
by MITRE • 10/06/2026
Mooncake Store master through 0.3.13.post1 contains a missing authorization vulnerability that allows unauthenticated attackers to inject completed LOCAL_DISK replicas through the NotifyOffloadSuccess RPC. Attackers can mount a local disk segment with a self-chosen client UUID, then attach replicas pointing at attacker-controlled endpoints to serve poisoned disk-tier reads and fake key existence.
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Analysis
by VulDB Data Team • 10/06/2026
The vulnerability identified in Mooncake Store versions up to 0.3.13.post1 represents a critical failure in access control mechanisms within the distributed storage system's replication protocol. Specifically, the NotifyOffloadSuccess Remote Procedure Call (RPC) endpoint lacks proper authentication and authorization checks, allowing any network-accessible actor to interact with it without valid credentials. This architectural flaw enables unauthenticated attackers to manipulate the state of the cluster by injecting completed LOCAL_DISK replicas into the metadata management layer. The core technical issue lies in the server's acceptance of replica completion notifications from arbitrary sources, failing to verify that the requesting entity is an authorized participant in the specific replication group or shard being modified.
By exploiting this missing authorization check, an attacker can mount a local disk segment and assign it a self-chosen client UUID, effectively masquerading as a legitimate storage node within the cluster. The attacker then attaches replicas pointing to endpoints they control, which allows them to serve poisoned responses for disk-tier reads. This capability fundamentally undermines the integrity of the data stored in Mooncake Store. Since the system trusts these injected replicas as valid copies of existing keys, an adversary can manipulate read operations by returning fabricated or corrupted data instead of the actual content. Furthermore, this manipulation extends beyond simple data corruption; attackers can fake key existence, causing the cluster to believe that specific data objects are present and replicated when they may not be, or vice versa.
The operational impact of this vulnerability is severe, affecting both confidentiality and integrity within the distributed storage environment. Attackers who successfully exploit this flaw can disrupt service availability by introducing inconsistent states across nodes, leading to potential data loss or corruption during subsequent replication cycles or failover events. The ability to fake key existence complicates debugging and recovery efforts, as standard consistency checks may incorrectly validate poisoned replicas against other legitimate copies if the attacker controls enough endpoints. This creates a persistent backdoor into the storage infrastructure that can be used for long-term espionage, data tampering, or preparation for more destructive attacks such as ransomware deployment by corrupting critical datasets.
From a classification perspective, this vulnerability aligns with CWE-287: Improper Authentication and CWE-345: Insufficient Verification of Data Authenticity. It also maps to MITRE ATT&CK techniques related to Initial Access via Exploitation of Remote Services and Defense Evasion through Masquerading, as the attacker uses a fabricated client UUID to blend in with legitimate traffic. To mitigate this risk, immediate patching to version 0.3.14 or later is required, where these authorization checks have been implemented. In environments where upgrading is not immediately feasible, network-level mitigations such as restricting access to the NotifyOffloadSuccess RPC endpoint via firewall rules or mutual TLS authentication can provide temporary protection. Additionally, implementing strict validation of client UUIDs against a whitelist of authorized nodes and auditing replication logs for anomalous replica injection patterns can help detect ongoing exploitation attempts.