Tags: regex
Rating:
For a better view check our [githubpage](https://bsempir0x65.github.io/CTF_Writeups/SEETF_CTF_2022/#regex101) or [github](https://github.com/bsempir0x65/CTF_Writeups/tree/main/SEETF_CTF_2022#regex101) out
This was actually one of the challenges which did not really have something to do with hacking. This was more or less a training task to recognize that being able to use regex expressions can be crucial. Based on the name of the challenge we thought this was a hint to use the site [regex101](https://regex101.com/) so that's what we did. So we "cat" the attached file to have all 2999 and copied them into regex101.
As you can see in the Screenshot we already have only one match with the regex \[A-Z\]\{5\}\[1-9\]\{5\}\[A-Z\]\{6\} which brings us the flag SEE{RGSXG13841KLWIUO}. On the right side you also have a nice explanation why this regex matches and what the single parts do. Play around a bit with it and use the references or the regex quiz on the left side to improve your regex skills.
