Improper Access Control in Cloudreve File Management System
CVE-2026-55502

7.1HIGH

Key Information:

Vendor

Cloudreve

Status
Cloudreve
Vendor
CVE Published:
31 July 2026

What is CVE-2026-55502?

Cloudreve is a self-hosted file management and sharing system that has an access control vulnerability affecting its OAuth token management. In versions prior to 4.17.0, the endpoint POST /api/v4/admin/policy/oauth/signin only requires Admin.Read permissions, allowing users to bypass the intended security controls. This vulnerability exists because the endpoint can be exploited to persist attacker-injected OneDrive secret and app_id values to modify storage policy credentials without needing Admin.Write permissions. Consequently, an unauthenticated attacker can manipulate storage configurations by using a valid OAuth URL. This issue was resolved in version 4.17.0, which introduces necessary permission checks to prevent unauthorized access.

Affected Version(s)

cloudreve < 4.17.0

References

https://github.com/cloudreve/cloudreve/security/advisorie...
x_refsource_CONFIRM

CVSS V3.1

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.