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Tracks / Traffic Analysis / The Silent Pixel

The Silent Pixel

Medium 35 pts

The lab loads a 1×1 image. The image is meaningless; the response that carries it is not. The server attaches a flag header and the page throws it away without looking. Catch it on the way in.

Hints

Open them in order. They nudge, they do not solve.

Hint 1

This one is in the response — the server's half of the conversation.

Hint 2

Reload the lab with the capture running; the image is fetched on every load.

Hint 3

Filter http.response, find the one returning an image, read its headers.

Your live lab

Plain HTTP on port 9080 — no TLS, so your capture is readable end to end. Start capturing on your Wi-Fi interface first, then open this and use the buttons.

Open the wire lab

Display filter: tcp.port == 9080

Submit the flag

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