Description

Unauthenticated Sensitive Data Exposure in Museder RestoreOne <= 2.7.276 versions.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.5",
  "pubDate": "2026-10-06T09:17:53.873Z",
  "pubdate": "2026-10-06T09:17:53.873Z",
  "executiveSummary": "Museder RestoreOne versions 2.7.276 and earlier are susceptible to an unauthenticated sensitive data exposure vulnerability. This flaw allows unauthorized remote attackers to bypass security controls and access sensitive information stored or processed by the application without requiring any form of authentication.\nThe vulnerability originates from a failure in the application's access control mechanisms, which do not properly enforce authorization checks for specific endpoints or resources. This creates a critical security risk, as sensitive data, including potential system configurations, user information, or proprietary business data, may be exposed to public or unauthorized access.\nSuccessful exploitation requires no specialized privileges or active sessions, making it highly attractive for attackers performing reconnaissance or data exfiltration. The risk implications are severe, potentially leading to a complete compromise of confidentiality regarding the data managed by the RestoreOne platform. Organizations utilizing this product are at immediate risk of information disclosure if these instances are exposed to untrusted network segments.",
  "technicalDetails": "The vulnerability exists due to an improper implementation of access control logic within Museder RestoreOne versions 2.7.276 and earlier. Specifically, the application fails to validate the authentication state of requests targeting sensitive backend functions or data retrieval endpoints.\nUnder normal operating conditions, these endpoints should be protected by middleware or session-validation hooks that verify the identity of the requesting user. However, due to insecure configuration or flawed code logic, these checks are either omitted or bypassable via crafted HTTP requests. Consequently, the application processes requests from unauthenticated entities as if they were originated by authorized users.\nThe attack flow involves an attacker identifying the exposed endpoints, likely through manual discovery or directory brute-forcing. Once identified, the attacker submits direct HTTP GET or POST requests to these endpoints without providing valid session tokens or credentials. Because the underlying server-side logic fails to perform an authorization verification, the application proceeds to execute the requested data retrieval function. The server then responds with the requested sensitive data, effectively disclosing internal information to the unauthorized requester.\nThis vulnerability is exacerbated by the lack of input validation or contextual awareness at the API layer. The affected component is the application's core data retrieval module, which remains susceptible regardless of the network-layer security controls if the instance is reachable. Post-exploitation, an attacker can systematically scrape exposed sensitive files, configuration strings, or user-related data, facilitating further stages of an attack chain, such as privilege escalation or lateral movement if credentials or tokens are exposed during this disclosure process.\nThe scope of impact is broad, as the vulnerability does not require prior knowledge of legitimate user accounts. It represents a fundamental breakdown in the Principle of Least Privilege and secure API design within the RestoreOne architecture."
}