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Web exploitationmedium200 pts0 solves

Predictable Reset Token

The Acme portal e-mails password-reset links. A leaked debug log and part of the source code are all you have. Can you work out the reset token that was sent for the admin account?

Learning objectives

Recognise weak token generation (guessable inputs, truncated MD5) and reproduce it from source and logs.

Instructions

Read reset_service.php and server.log. The flag is cspk{TOKEN} where TOKEN is the token generated for the admin request (12 characters). Compute it offline.

Prerequisites: Reading short PHP or pseudo-code; an MD5 command such as md5sum or Python hashlib.
Flag format: cspk{12 hex characters}
Files: reset_service.php (0.6 KB), server.log (0.6 KB) (download after registering)
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References

Write-up

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