CVE-2026-33195
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk43th percentile - higher than 43% of all known CVEs
Summary
A path traversal vulnerability in Active Storage's `DiskService#path_for` allows arbitrary file access when blob keys contain `../` sequences. Attackers can read, write, or delete files outside the storage root directory.
Risk Assessment
The organization risks unauthorized file system access, potentially leading to data breaches, configuration tampering, or deletion of critical assets.
Recommendation
Upgrade Active Storage to versions 8.1.2.1, 8.0.4.1, or 7.2.3.1 immediately. If not possible, ensure blob keys are never derived from untrusted input.
Original NVD description (English source)
Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, Active Storage's `DiskService#path_for` does not validate that the resolved filesystem path remains within the storage root directory. If a blob key containing path traversal sequences (e.g. `../`) is used, it could allow reading, writing, or deleting arbitrary files on the server. Blob keys are expected to be trusted strings, but some applications could be passing user input as keys and would be affected. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.