CVE-2026-77165 in Server
Summary
by MITRE • 09/21/2026
File owners were unable to unlock TYPE_TOKEN locks placed by other users, leaving files permanently locked with no recovery path outside of the database.
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Analysis
by VulDB Data Team • 09/21/2026
The vulnerability described involves a critical failure in file locking mechanisms within a specific software system, where type token-based access controls prevent legitimate file owners from unlocking resources that have been secured by other users. This issue represents a significant flaw in the application's concurrency and resource management logic, effectively creating a denial of service condition for authorized personnel who require immediate access to their own files. The core technical deficiency lies in the permission validation hierarchy used when attempting to release locks; rather than prioritizing ownership or implementing a robust administrative override mechanism that respects user identity alongside lock status, the system strictly enforces exclusive control by the locking entity without adequate safeguards against misuse or accidental retention of locks.
From a vulnerability classification perspective, this issue aligns with CWE-862 Missing Authorization, as the application fails to properly enforce access controls for file unlocking operations based on ownership attributes. Furthermore, it relates to CWE-754 Improper Check for Unusual or Exceptional Conditions, specifically regarding the handling of edge cases where lock contention occurs between different user identities without a defined resolution path. The inability to recover locked files outside of direct database manipulation indicates a lack of proper error handling and recovery procedures, which is characteristic of CWE-209 Generation of Error Message Containing Sensitive Information if such errors expose internal states, or more broadly CWE-832 Unlocking Lock that Is Not Locked if the system allows inconsistent state transitions.
The operational impact of this vulnerability is severe for any organization relying on the affected software for collaborative workflows. When a file owner cannot unlock a resource locked by another user, business processes are halted until an administrator intervenes with low-level database access to manually clear the lock records. This dependency on manual intervention introduces significant latency and increases the risk of human error during recovery efforts. In high-throughput environments or systems supporting concurrent editing, such as document management platforms or collaborative development tools, this flaw can lead to substantial productivity losses and potential data integrity issues if users attempt workarounds that bypass standard locking protocols.
This behavior also poses a security risk by encouraging insecure practices among system administrators who may resort to direct database modifications rather than using supported application interfaces. Such actions can violate audit trails and compromise the consistency of metadata associated with file states, potentially leading to further vulnerabilities like CWE-693 Protection Mechanism Failure where the intended control is bypassed through unauthorized means. The lack of a programmatic recovery path suggests that the locking mechanism does not integrate well with broader identity management systems or role-based access controls that might otherwise allow for emergency overrides by designated security roles.
To mitigate this vulnerability, developers should implement a hierarchical authorization model that distinguishes between lock creation rights and unlock privileges based on file ownership or administrative roles. The system must include an explicit API endpoint or interface function allowing file owners to release locks held by other users after verifying their identity through multi-factor authentication or session validation. Additionally, implementing automatic lease expiration for type token locks would prevent indefinite locking scenarios caused by client crashes or network interruptions. Integrating these changes with existing audit logging frameworks ensures that all unlock attempts are recorded and monitored, aligning the system with industry standards such as NIST SP 800-53 AC-4 which mandates separation of duties and proper access enforcement mechanisms to maintain operational integrity.