CVE-2026-13061 in Server
Summary
by MITRE • 07/22/2026
An authenticated user may be able to view session metadata belonging to other users on the system through the $listSessions aggregation stage. This information is normally restricted to users with cluster-level administrative privileges, and includes active session identifiers, associated usernames, and activity timestamps.
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Analysis
by VulDB Data Team • 07/22/2026
This vulnerability represents a critical privilege escalation issue that undermines the fundamental security boundaries of authentication systems. The flaw exists within the session management component where an authenticated user can exploit the $listSessions aggregation stage to access metadata belonging to other users on the system. This represents a direct violation of the principle of least privilege and demonstrates a severe authorization bypass mechanism that allows lateral movement between user sessions.
The technical implementation of this vulnerability stems from improper access control validation within the aggregation pipeline functionality. When users execute the $listSessions operation, the system fails to properly verify whether the requesting user has appropriate authorization levels to view session information for other accounts. The affected metadata includes sensitive session identifiers such as session tokens and unique identifiers that can be used to impersonate legitimate users, along with associated usernames that reveal system user composition and activity timestamps that provide insights into user behavior patterns.
The operational impact of this vulnerability extends beyond simple information disclosure, creating a pathway for sophisticated attacks that can lead to full system compromise. An attacker with basic authenticated access could potentially gather intelligence about active user sessions, identify high-value accounts through session activity patterns, and correlate this information with other reconnaissance efforts. The exposure of session identifiers provides the foundation for session hijacking attacks, while username information enables targeted social engineering and credential stuffing operations.
This vulnerability aligns with CWE-285 which addresses improper authorization issues in software systems, specifically targeting the failure to properly enforce access controls during resource enumeration operations. The flaw also maps to ATT&CK technique T1078 which covers valid accounts as a means for gaining access, since the compromised session metadata can be leveraged to maintain persistent access or escalate privileges within the system.
Mitigation strategies should focus on implementing robust access control checks at the aggregation stage level, ensuring that only users with appropriate cluster-level administrative privileges can execute $listSessions operations. Organizations should enforce mandatory access controls that validate user permissions against session resources before allowing metadata retrieval, implement session isolation mechanisms, and establish monitoring for unauthorized session enumeration attempts. Additionally, system administrators should regularly audit session management configurations and ensure that privilege boundaries are properly enforced through comprehensive testing of authorization logic.