CVE-2026-112769 in parse-server
Summary
by MITRE • 10/19/2026
Parse Server before 8.6.98 and 9.0.0 before 9.10.3-alpha.1 does not enforce the create and addField class-level permissions of the _Session class when creating sessions. An authenticated user, or anyone holding that user's session token, can send POST requests to /sessions or /classes/_Session to create additional sessions for that user and add fields to _Session; these sessions are not revoked when the original session is logged out.
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Analysis
by VulDB Data Team • 10/19/2026
The identified vulnerability resides within Parse Server versions prior to 8.6.98 and 9.0.0 before 9.10.3-alpha.1, specifically affecting the handling of class-level permissions for the _Session class. The core technical flaw is a failure in permission enforcement during session creation and field modification operations. Specifically, when an authenticated user or any entity possessing that user's valid session token issues POST requests to endpoints such as /sessions or /classes/_Session, the server incorrectly allows these actions without verifying whether the requesting principal has the necessary create or addField permissions defined for the _Session class in the application configuration. This represents a significant deviation from the principle of least privilege and proper access control enforcement mechanisms inherent in secure session management systems.
From an operational perspective, this misconfiguration enables an attacker who possesses a valid user session token to perform unauthorized actions beyond simple data retrieval or modification of existing records. The ability to create additional sessions for the same user account effectively allows for session proliferation without triggering standard revocation protocols. Furthermore, the capability to add arbitrary fields to _Session objects can be leveraged to inject malicious metadata into the session object itself. These newly created sessions remain active and valid even after the original primary session is explicitly logged out or revoked by the application logic. This persistence of access means that once an attacker obtains a single token, they can maintain persistent unauthorized access to the user's account resources indefinitely, bypassing standard logout mechanisms designed to terminate all associated authentication states.
The security implications are severe, as this vulnerability directly compromises session integrity and availability. It facilitates privilege escalation in contexts where multiple sessions might be used for different purposes or devices, allowing an attacker to create hidden backdoor sessions that survive user-initiated logouts. This behavior aligns with CWE-269, which describes Improper Privilege Management, specifically the failure to enforce required permissions during critical operations. Additionally, the ability to maintain access after logout corresponds to ATT&CK technique T1078, Valid Accounts, particularly in the context of persistence through session manipulation. The lack of revocation for derived sessions undermines the fundamental trust model of stateful authentication systems, where a single point of compromise can lead to prolonged unauthorized access.
To mitigate this vulnerability, administrators must upgrade Parse Server immediately to version 8.6.98 or later, or if using the 9.x branch, to version 9.10.3-alpha.1 and above. These updated versions correct the permission checking logic for class-level operations on the _Session collection. In environments where upgrading is not immediately feasible, temporary mitigations should focus on restricting network access to Parse Server endpoints to trusted IP ranges if possible, although this does not fully address the issue since authenticated users are already within the trust boundary. It is also critical to review application logic for any reliance on session count or uniqueness assumptions that might be exploited by this flaw. Regular audits of class-level permissions should ensure that sensitive classes like _Session have strict create and addField restrictions set to false unless explicitly required by specific, verified use cases, thereby enforcing defense-in-depth principles even if server-side checks are bypassed through other vectors.