By using the commands binwalk and file, we found no results![](https://i.loli.net/2020/07/08/DHLzaXwnNkfMbW1.png)Based on the title, we're guessing it might be an inversion of hexadecimal.Here we use the strrev function in PHP for this.![](https://i.loli.net/2020/07/08/qSJMcaFmRTCilb3.png)After processing, I opened it and found that it was still reporting an error, considered using winhex to view it, and found that it was a jpg file, so I added the file header(ffd8ff)![](https://i.loli.net/2020/07/08/uHgpijreytaSC28.png)Continued to find hints that it is RC4 encryption, but still no flag. test is not LSB steganography, etc. continued winhex view.![](https://i.loli.net/2020/07/08/1EOcZpewAFDNXTM.png)Suspicious strings foundxoBTuw36SfH4hicvCzFD9ESj![](https://i.loli.net/2020/07/08/HF6Et3lYbc7zegv.png)
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