Description

An issue in MongoDB Server could allow an authenticated user with a limited database-scoped role to perform an action against protected system collections that should require more specific privileges. This could result in exposure of collection metadata and, on certain deployment configurations, unauthorized modification of system collection data.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.4",
  "pubDate": "2026-08-11T19:17:24.120Z",
  "pubdate": "2026-08-11T19:17:24.120Z",
  "executiveSummary": "An authorization bypass vulnerability has been identified in MongoDB Server that allows an authenticated user assigned a limited, database-scoped role to execute unauthorized operations against protected system collections.\nUnder standard security paradigms, interacting with and modifying system-level collections demands elevated, specific administrative privileges. However, this authorization enforcement flaw enables low-privileged principals to circumvent these restrictions.\nThe primary impact of successful exploitation includes the unauthorized exposure of sensitive collection metadata and, depending on the specific deployment configuration, the potential unauthorized modification or tampering of system collection data.\nThe risk implications are significant for multi-tenant or least-privilege environments where database-scoped users are provisioned with restricted permissions, as it breaks the isolation boundaries between standard database operations and critical system administration.\nAttacker capabilities are constrained by the prerequisite of having an authenticated session with a limited database-scoped role, meaning unauthenticated external entities cannot directly trigger this condition without prior credential compromise.",
  "technicalDetails": "The vulnerability stems from an authorization enforcement failure within the access control component of MongoDB Server when processing requests targeted at protected system collections.\nThe vulnerable component is responsible for validating the caller privileges against the requested database-scoped operations. The root cause lies in insufficient privilege validation checks, where requests originating from a limited database-scoped role are incorrectly permitted to interact with system collections that inherently mandate stricter, more granular authorization checks.\nThe attack flow proceeds as follows: First, the adversary authenticates to the MongoDB Server using credentials associated with a limited, database-scoped role. Second, the user crafts and transmits a database command or query explicitly targeting protected system collections. Third, due to the flawed privilege validation logic within the server's authorization subsystem, the request bypasses the expected permission gates. Finally, the database engine processes the command, returning restricted collection metadata or applying unauthorized modifications to the underlying system collection data depending on the deployment configuration.\nExploitation requirements dictate that the attacker must possess valid authentication credentials and an existing database-scoped role within the target deployment.\nThe post-exploitation impact includes the breach of data confidentiality via exposed metadata and the potential compromise of data integrity through unauthorized modifications to system-level storage, which could affect overall database stability and security state."
}