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Lab 162 — VaultDrop — File Upload Race Condition (TOCTOU)

hackadvisor

Task: PHP file sharing platform with avatar upload and asynchronous security scanning — TOCTOU race condition in file validation. Solution: upload PHP webshell with spoofed Content-Type, race the async scanner by immediately requesting the uploaded file URL before deletion, achieve RCE and read /root/flag.txt.

$ ls tags/ techniques/
race_condition_uploadtoctou_file_upload_bypassphp_webshell_executionasync_scan_race_windowanti_bot_honeypot_evasioncontent_type_spoofing

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