Description
Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, ViewerSessionValidation uses only the session-id prefix of a WOPI access token and does not enforce the requested viewer action, allowing a malicious or compromised WOPI viewer with a view session to forge the token suffix and invoke WOPI write routes for the underlying file. This issue is fixed in version 4.17.0.
References4
Metrics
- CVSS 3.1
-
6.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:H/A:N - EPSS — exploit probability
- 0% percentile: 24 · as of 13 November 2026
- CWE
- CWE-863
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