CVE-2026-77637: Cloudreve

Low severity, CVSS 3.8. EPSS: 0.3% chance of exploitation in the next 30 days.

Cloudreve is a self-hosted file management and sharing system. Prior to 4.18.0, tool.GET("wopi") and tool.POST("mail") in routers/router.go inherit ScopeAdminRead but omit the RequiredScopes(types.ScopeAdminWrite) middleware applied to neighboring state-changing admin tool routes. An OAuth application or API key limited to Admin.Read can therefore probe configured WOPI service endpoints and send arbitrary test email through the server SMTP configuration, exceeding the token's intended read-only authorization boundary. This issue is fixed in version 4.18.0.

Affected products

• Cloudreve Cloudreve: before 4.18.0 (fixed in 4.18.0)

Published 2026-09-22. Last modified 2026-09-22.