Cloudreve: Storage-quota TOCTOU race allows quota bypass and storage-based denial of service

Summary Cloudreve v4 splits the storage-quota check reading the user's used bytes and comparing them to MaxStorage and the charge incrementing users.storage into two non-atomic steps in the PrepareUpload code path. This creates a Time-of-Check to Time-of-Use TOCTOU race condition. Any authenticat...

GHSA-XJ3H-WWXQ-GFCJ Cloudreve: Storage-quota TOCTOU race allows quota bypass and storage-based denial of service

Summary Cloudreve v4 splits the storage-quota check reading the user's used bytes and comparing them to MaxStorage and the charge incrementing users.storage into two non-atomic steps in the PrepareUpload code path. This creates a Time-of-Check to Time-of-Use TOCTOU race condition. Any authenticat...

CVE-2026-77633

Cloudreve is a self-hosted file management and sharing system. Prior to 4.18.0, PrepareUpload in pkg/filemanager/fs/dbfs/upload.go checks a stale in-memory user storage value through validateUserCapacity and later applies an unconditional storage charge outside the same quota-enforcing transactio...

CVE-2026-77633

Cloudreve , a self-hosted file management and sharing system, contains a TOCTOU race condition in PrepareUpload (pkg/filemanager/fs/dbfs/upload.go) prior to version 4.18.0. The function checks a stale in-memory storage value via validateUserCapacity, then applies an unconditional storage charge o...

CVE-2026-77633 Cloudreve: Storage-quota TOCTOU race allows quota bypass and storage-based denial of service

Cloudreve is a self-hosted file management and sharing system. Prior to 4.18.0, PrepareUpload in pkg/filemanager/fs/dbfs/upload.go checks a stale in-memory user storage value through validateUserCapacity and later applies an unconditional storage charge outside the same quota-enforcing transactio...

CVE-2026-77633 Cloudreve: Storage-quota TOCTOU race allows quota bypass and storage-based denial of service

Cloudreve is a self-hosted file management and sharing system. Prior to 4.18.0, PrepareUpload in pkg/filemanager/fs/dbfs/upload.go checks a stale in-memory user storage value through validateUserCapacity and later applies an unconditional storage charge outside the same quota-enforcing transactio...

PT-2026-96795

Name of the Vulnerable Software and Affected Versions Cloudreve versions prior to 4.18.0 Description An authenticated user with Files.Write permission can exploit a Time-of-Check to Time-of-Use TOCTOU race condition in the PrepareUpload function within pkg/filemanager/fs/dbfs/upload.go. The syste...

CVE-2026-77633: Concurrent Execution using Shared Resource with Improper Synchronization

Cloudreve is a self-hosted file management and sharing system. Prior to 4.18.0, PrepareUpload in pkg/filemanager/fs/dbfs/upload.go checks a stale in-memory user storage value through validateUserCapacity and later applies an unconditional storage charge outside the same quota-enforcing transactio...