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mission · xxe-filtered-svg

The Upload Filter (Blind XXE)

DropZone patched the avatar upload after the last report — the validator now rejects SVGs whose DOCTYPE mentions SYSTEM or any file path. But it still accepts SVG files, and the parser still expands external entities. You can't read a file back in the response anymore… so make the server send it somewhere you're listening.

objective

Exfiltrate the contents of /etc/hostname using blind XXE — your SVG can't read files back in the response, so exfiltrate out-of-band to your listener.

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DropZoneProfiledocs · helpyou@dropzone.app
Profilesigned in as you@dropzone.app

Your profile picture is shown on the team page. We accept PNG, JPG and SVG.

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attacker.hp-lab.local — listening
Exfiltration log

No requests captured yet. Plant a payload that calls fetch()…

Simulated target for training. This page is the vulnerable website — payloads you craft execute here in your browser. Practice only on systems you own or are authorized to test.