I recently came across a HMGCC recruitment pen with a curious message printed along the side. It seemed to be a small hexadecimal puzzle, which piqued my curiosity enough to see if I could decode it.
After manually transcribing the hexadecimal values from the pen, I first played around in CyberChef to get a feel for how the message might be encoded. Once I had a likely approach, I wrote a short Python script to put the decoding steps somewhere concrete:
- Convert each transcribed byte into fixed-width binary, because the printed hex values looked like byte-sized data rather than decimal numbers or plain text.
- Concatenate the binary values into one bitstream, because the first direct conversion to eight-bit ASCII did not produce a readable message.
- Split the bitstream into seven-bit chunks, because seven-bit ASCII was a plausible alternative encoding and kept the character boundaries consistent.
- Treat each chunk as ASCII, because that was the simplest way to test whether the regrouped bits represented text.
That revealed the message: Realise your cyber future.......