MontFerret ferret versions before 2.0.0-alpha.4 contain a path traversal vulnerability (CWE-22) in the IO::FS::WRITE function. When scraping websites that return filenames with '../' sequences, an attacker can manipulate output paths and write arbitrary files to the filesystem. This improper limitation of pathname allows overwriting or creating files outside intended directories, which can be leveraged for remote code execution by modifying critical files such as cron jobs or SSH keys. The issue is resolved in version 2.0.0-alpha.4.

An attacker controlling a malicious website can exploit this vulnerability to write arbitrary files on the system running Ferret. This can lead to remote code execution by modifying files that influence system or user behavior, such as cron jobs, SSH authorized_keys, or shell profiles. The vulnerability has a high CVSS score of 8.1, indicating significant impact on integrity and availability if exploited.

Upgrade MontFerret ferret to version 2.0.0-alpha.4 or later, where this path traversal vulnerability is fixed. Since no official patch links or vendor advisory details are provided, users should verify the update availability from MontFerret's official sources. Until upgraded, avoid scraping untrusted websites that may return filenames with '../' sequences or sanitize filenames before use to prevent path traversal.