CVE-2026-64825
CriticalCVSS 9.3Exploitation Probability (EPSS)
Low risk39th percentile - higher than 39% of all known CVEs
Summary
Home Assistant Core before version 2026.6.0 contains a path traversal vulnerability that allows unauthenticated attackers to write arbitrary files to any directory on the host filesystem by uploading a crafted backup archive during the initial onboarding window. Attackers can manipulate the 'name' field inside the uploaded archive's backup.json to supply an absolute path, causing pathlib.Path.__truediv__ to discard the configured backup directory prefix and write attacker-controlled content to arbitrary locations, with full filesystem access when the process runs as root.
Risk Assessment
The risk for the organization includes potential full system compromise, as an unauthenticated attacker can overwrite critical system files, add malicious scripts, or modify configuration, leading to data integrity and confidentiality breaches and possible host takeover.
Recommendation
Immediately upgrade Home Assistant Core to version 2026.6.0 or later. If upgrading is not possible, temporarily disable the backup restore functionality during the initial onboarding window or restrict network interface access to trusted IP addresses only.
Original NVD description (English source)
Home Assistant Core before 2026.6.0 contains a path traversal vulnerability that allows unauthenticated attackers to write arbitrary files to any directory on the host filesystem by uploading a crafted backup archive during the initial onboarding window. Attackers can manipulate the 'name' field inside the uploaded archive's backup.json to supply an absolute path, causing pathlib.Path.__truediv__ to discard the configured backup directory prefix and write attacker-controlled content to arbitrary locations, with full filesystem access when the process runs as root.