CVE-2026-103470 in Grouper
Summary
by MITRE • 09/30/2026
In Internet2 Grouper before 7.5.1 (in some configurations), a user who is allowed to create or edit rules in the User Interface can escalate privileges.
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Analysis
by VulDB Data Team • 09/30/2026
The vulnerability identified within Internet2 Grouper versions prior to 7.5.1 represents a critical privilege escalation flaw rooted in insufficient access control validation during rule management operations. Grouper serves as a widely adopted identity and access management solution, facilitating the creation of groups and assignment of permissions across complex organizational structures. The specific weakness arises when users are granted explicit privileges to create or edit rules through the web-based user interface. While these permissions are intended for managing group membership logic or attribute assignments rather than administrative system configuration, the underlying implementation fails to adequately distinguish between rule-level actions and higher-level privilege modifications. This architectural oversight allows an authenticated actor with standard editing rights to manipulate internal state in a manner that bypasses expected authorization boundaries, effectively granting them elevated privileges beyond their assigned role.
From a technical perspective, this flaw aligns closely with CWE-269, which describes Improper Control of Administrative Privilege. The vulnerability likely stems from the application logic failing to enforce strict separation between user-level rule definitions and system-wide administrative controls. When a user submits data to create or modify a rule via the API endpoint exposed by the UI, the backend processing does not sufficiently validate whether the resulting state change violates higher-order security policies. In many identity management systems, rules can indirectly influence access decisions for sensitive resources. If an attacker can craft a rule that alters how permissions are evaluated or assigned, they may inadvertently or intentionally trigger code paths that update administrative settings, such as modifying group ownership, altering policy enforcement mechanisms, or granting themselves membership in privileged groups. This bypasses the intended role-based access control model because the system trusts the user's input without verifying if the action exceeds their authorized scope of influence.
The operational impact of this vulnerability is severe for organizations relying on Grouper to enforce security boundaries. An attacker who exploits this flaw can escalate their privileges from a standard member or rule editor to an administrator-level role. This escalation enables unauthorized access to sensitive data, modification of critical group memberships, and potential disruption of identity services across the enterprise. Since Grouper often integrates with broader authentication frameworks like Shibboleth or Active Directory, compromising its integrity can lead to widespread lateral movement within the network infrastructure. The attacker could establish persistent backdoors by creating rules that automatically grant access to specific accounts under certain conditions, making detection difficult without comprehensive audit logging and behavioral analysis tools.
Mitigation strategies must prioritize immediate version upgrades alongside robust configuration hardening. Organizations running affected versions should upgrade to Grouper 7.5.1 or later, where the vendor has addressed these authorization checks to ensure that rule editing operations remain strictly confined to their intended scope. In environments where upgrading is not immediately feasible, administrators should restrict UI access for rule creation and editing to a minimal set of trusted administrative accounts rather than broad user groups. Additionally, implementing strict audit logging for all rule modification events can aid in detecting anomalous activities indicative of exploitation attempts. Security teams should also review existing rules for any that grant excessive permissions or rely on complex logic that might be abused, ensuring adherence to the principle of least privilege across all identity management configurations.