Fix path traversal in download_dir via server-controlled filenames#81
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OscarAkaElvis merged 1 commit intoJun 1, 2026
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download_dir() uses filenames from Get-ChildItem stdout directly in File.join() to construct local paths. A rogue server can return names containing ../ sequences, writing files outside the download directory. Use File.basename() on server-supplied filenames for the local path to strip directory components while preserving the original name for the remote download path.
Collaborator
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Thanks for the PR and for reporting this issue. Could you please re-submit the PR against the Once it is opened against Thanks again for the contribution. |
Author
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Done -- rebased the PR to target |
Member
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I've been doing some tests and everything looks good to me. Merging. |
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Summary
download_dir()parses filenames fromGet-ChildItemstdout and passes them directly toFile.join()to build local file paths../sequences (e.g.../../.ssh/authorized_keys), causing files to be written outside the intended download directoryFile.joindoes not sanitize traversal sequences:File.join("/home/user/loot", "../../.ssh/authorized_keys")resolves to/home/user/.ssh/authorized_keysFix
Use
File.basename()on server-supplied filenames for the local path construction only. The remote download path still uses the original filename so the correct file is fetched. Entries that resolve to empty,., or..are skipped.Steps to reproduce
Get-ChildItemdownload C:\loot\*../../.ssh/authorized_keys~/.ssh/authorized_keysinstead of the download directory