Executive brief
Synology Hyper Backup is a tool used to back up data from Synology NAS devices to various destinations. A security flaw in the backup task management allows an authorized user to bypass folder restrictions and write files to unintended locations on the system. This could lead to unauthorized modification of system files or data corruption, though it requires the attacker to already have a valid user account.
Technical details
A path traversal vulnerability (CWE-22) exists in the Backup Task functionality of Synology Hyper Backup. The root cause is improper validation of user-supplied pathnames, allowing them to escape the intended directory scope. An authenticated remote attacker with low privileges can exploit this via unspecified vectors to write specific files to restricted directories. The vulnerability is addressed in Hyper Backup version 4.1.2-4036 and later.
Affected products
- Synology Hyper Backup before 4.1.2-4036
Timeline
- 2026-06-03: advisory: NVD and Synology published the advisory details.
- 2026-06-03: disclosed