CVE-2026-104949 in WarehousePG
Summary
by MITRE • 10/21/2026
WarehousePG (WHPG) 6.27.1 through 6.27.6 and 7.2.1 through 7.6.0 are affected by a missing authorization vulnerability (CWE-862) in gp_add_coordinator_standby(). The function is named gp_add_master_standby() in WHPG 6, and WHPG 7 keeps that name as an alias. Unlike the other segment add and remove functions, it does not require superuser privileges. A low-privileged user who can open a utility-mode connection can use it to add a fake standby coordinator entry to gp_segment_configuration on a cluster that has no standby configured. Administrators then cannot add a real standby until a superuser removes the fake entry. User data is not exposed or modified.
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Analysis
by VulDB Data Team • 10/21/2026
The vulnerability identified in WarehousePG versions 6.27.1 through 6.27.6 and 7.2.1 through 7.6.0 represents a critical failure in access control mechanisms, specifically categorized under CWE-862 as Missing Authorization. This flaw resides within the gp_add_coordinator_standby function, which serves to register standby coordinator nodes for high availability configurations. In WarehousePG version 6, this functionality is exposed via the alias gp_add_master_standby, a naming convention retained in version 7 for backward compatibility. The core technical deficiency lies in the privilege requirements associated with these functions; unlike other segment management operations that strictly enforce superuser privileges to prevent unauthorized structural changes to the database cluster configuration, this specific function allows execution by low-privileged users who possess utility-mode connection capabilities. This discrepancy creates a significant security gap where standard database users can execute administrative-level commands intended exclusively for system administrators.
The operational impact of this vulnerability centers on denial of service and configuration integrity compromise rather than data confidentiality or modification breaches. A malicious actor with limited privileges can exploit the function to inject a fake standby coordinator entry into the gp_segment_configuration table, particularly in environments where no legitimate standby is currently configured. This action effectively pollutes the cluster's high availability metadata. The immediate consequence is that system administrators are unable to add a genuine standby node because the configuration already contains an invalid or placeholder entry representing the non-existent standby. To restore proper functionality and allow for the deployment of actual redundancy measures, a superuser must manually intervene to remove the fabricated entry from the database catalog. This process introduces unnecessary downtime and operational overhead while leaving the cluster vulnerable during the remediation window.
From a threat modeling perspective, this vulnerability aligns with ATT&CK techniques related to Defense Evasion and Impact, specifically those involving configuration manipulation or resource hijacking that disrupt service availability. Although user data remains untouched and no sensitive information is exfiltrated, the ability of an unprivileged user to alter critical cluster metadata undermines the principle of least privilege and compromises the integrity of the database infrastructure's high-availability setup. The lack of proper authorization checks allows for a persistent state change that requires elevated privileges to reverse, effectively creating a self-inflicted denial of service condition that only administrators can resolve.
Mitigation strategies should prioritize immediate patching to versions beyond 6.27.6 and 7.6.0 where this access control flaw has been addressed by enforcing superuser requirements for the gp_add_coordinator_standby function. In environments where upgrading is not immediately feasible, administrative controls must be tightened by restricting utility-mode connections to only those users who require them for legitimate maintenance tasks. Additionally, database administrators should implement rigorous monitoring of changes to the gp_segment_configuration table and audit logs related to standby coordinator registrations to detect any unauthorized attempts to inject fake entries. Regular review of user privileges ensures that low-privileged accounts do not possess unnecessary access to administrative functions, thereby reducing the attack surface for such authorization bypass vulnerabilities.