Claude Code falls short to Codex in FRA cryptographic challenge

The Swedish National Radio Intelligence Administration released a report on solving the first task in their annual competition. The test pitted Claude Code and Codex against each other. Codex emerged victorious, solving the task in two minutes.
The challenge involved finding a hidden flag on a webpage. Both agents quickly realized the key was hidden in an image on the page footer. Codex spotted nearly imperceptible pixels at the top of the image, increased contrast with ImageMagick, and read the flag.
Claude Code failed due to overanalysis. It misinterpreted the image as an audiogram and wasted time on spectral analysis of sound waves. Ultimately, the model missed the simple visual cue and couldn't extract the hidden text.
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