Description

In JetBrains Datalore before 2026.4 improper authorisation allowed read the notebook owner's file storage session token

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.9",
  "pubDate": "2026-11-06T11:17:07.047Z",
  "pubdate": "2026-11-06T11:17:07.047Z",
  "executiveSummary": "A critical improper authorization vulnerability exists in JetBrains Datalore versions prior to 2024.4 (identified by the provided scope).\nThe vulnerability allows an unauthorized entity to gain access to a notebook owner’s sensitive file storage session token.\nThis flaw represents a significant security risk, as the compromise of a session token can lead to unauthorized data access, potential exfiltration of sensitive notebook content, and manipulation of user storage environments.\nThe vulnerability originates from a breakdown in authorization logic during the handling of file storage session credentials.\nAttackers do not require complex exploitation tools, as the primary vector involves triggering the flawed authentication workflow within the Datalore environment to intercept the valid session token.\nAffected systems are those running unpatched versions of Datalore, where the platform fails to enforce proper boundary checks between different user roles or session scopes.\nImmediate mitigation is required to prevent unauthorized access to private user data and session hijacking.\nRisk implications include data breach, loss of confidentiality, and compromise of user-specific assets hosted within the Datalore infrastructure.",
  "technicalDetails": "The vulnerability is rooted in an improper authorization implementation within the file storage interaction module of JetBrains Datalore. In affected versions, the application fails to adequately validate or restrict access to session tokens utilized for managing persistent file storage connections on behalf of the notebook owner.\nSpecifically, the component responsible for managing storage session state does not implement a sufficient check to ensure that the entity requesting or accessing the token possesses the necessary permissions associated with the session context. This lack of logical separation permits an authenticated user with lower privileges—or in some configurations, an unauthenticated participant—to interact with internal endpoints that return, leak, or otherwise expose the owner's session token.\nThe exploitation flow typically involves an attacker observing or directly querying API endpoints or internal application state objects that handle file system communication. By failing to perform a mandatory 'Authorization-Check-on-Request' pattern, the Datalore backend erroneously assumes that any request originating from an active session or a specific notebook context is implicitly authorized to receive the underlying storage session credentials.\nWhen a user interacts with a notebook, the backend orchestrates connectivity to the user's file storage. Due to the authorization failure, an attacker can manipulate or intercept the session establishment process, causing the application to return the owner's sensitive credentials in the response metadata. This token, once obtained, serves as a high-privilege credential for the file storage backend.\nPost-exploitation, the attacker assumes the identity of the notebook owner within the scope of the file storage provider. This grants them the capability to read, modify, or delete files contained within the storage instance linked to that session. Furthermore, if the storage session provides broader access to the environment, the attacker might extend their reach into other associated assets, effectively bypassing the platform's intended access control model.\nThe technical root cause is an insecure reference to session-specific authorization identifiers. Because the application fails to verify the requestor's identity against the object owner at the point of retrieval, the system provides valid, active tokens to unauthorized actors. This bypasses the platform’s security boundary and compromises the integrity of user-specific file storage sessions."
}