CVE-2026-85973 in MarkLogic Server
Summary
by MITRE • 10/12/2026
Progress MarkLogic Server 12.x releases before 12.1.0 may use cleartext transport for certain cluster-management communications. A network-positioned attacker could intercept or modify information transmitted through an affected connection.
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Analysis
by VulDB Data Team • 10/12/2026
The vulnerability identified in Progress MarkLogic Server versions prior to release 12.1.0 involves the improper implementation of secure communication protocols within the database clustering architecture. Specifically, certain cluster-management communications are transmitted using cleartext transport mechanisms rather than encrypted channels such as TLS or SSL. This architectural flaw allows data exchanged between nodes in a MarkLogic cluster to be visible to any entity capable of monitoring network traffic on the same segment or through intermediate routing points. The issue is particularly critical because cluster management traffic often contains sensitive operational metadata, configuration updates, and potentially authentication tokens required for node coordination and failover processes.
From a technical perspective, this deficiency represents a failure to enforce confidentiality and integrity controls during inter-node communication. In distributed database systems like MarkLogic, nodes must constantly exchange heartbeats, state information, and query routing data to maintain cluster consistency and availability. When these exchanges occur over unencrypted connections, they are susceptible to passive eavesdropping and active man-in-the-middle attacks. An attacker positioned on the network path can intercept these packets to extract sensitive operational details or modify them to disrupt service availability, cause split-brain scenarios, or inject malicious commands into the cluster management plane. This lack of encryption violates fundamental security principles regarding data protection in transit, especially for administrative and control-plane traffic which typically requires higher levels of trust and secrecy than standard application-level queries.
The operational impact of this vulnerability is significant for organizations relying on MarkLogic clusters for high-availability deployments or sensitive data processing. A network-positioned attacker could exploit this weakness to perform reconnaissance by analyzing cluster topology, node roles, and internal communication patterns. More severely, the ability to modify transmitted information opens the door to denial-of-service conditions through manipulation of heartbeats or quorum mechanisms, potentially causing nodes to incorrectly assume other nodes are down and triggering unnecessary failovers or data splits. In worst-case scenarios, if authentication credentials or session tokens are included in these cleartext streams, an attacker could gain unauthorized access to cluster management interfaces or escalate privileges within the database environment by replaying captured valid sessions.
This vulnerability aligns with CWE-319, which classifies Cleartext Transmission of Sensitive Information as a common weakness where data is sent without adequate cryptographic protection. Furthermore, it relates to ATT&CK technique T1048, Exfiltration Over Alternative Protocol, although in this context the primary risk is interception and modification rather than just exfiltration. The vulnerability also touches upon principles outlined in NIST SP 800-52 regarding TLS implementation guidelines, which mandate encryption for all administrative and management interfaces to prevent unauthorized access and data leakage.
To mitigate this risk, organizations running affected versions of MarkLogic Server should immediately upgrade to version 12.1.0 or later, where the issue has been resolved by enforcing encrypted transport for cluster-management communications. Until an upgrade is feasible, administrators can implement network-level mitigations such as placing cluster nodes in isolated VLANs with strict access control lists that restrict inter-node traffic to only authorized ports and protocols. Additionally, deploying intrusion detection systems capable of identifying cleartext database management traffic on monitored segments can provide early warning indicators of potential exploitation attempts. It is also advisable to review firewall rules to ensure that no external or untrusted networks have connectivity to the cluster management interfaces, thereby reducing the attack surface available for network-positioned adversaries.