security

UK pentester 'killa' claims $2K Bitcoin prize in PHP2Shell capture-the-flag contest

Jaydip Modhwadia beats challenge designed to test real-world exploitability of PHP2Shell in around 3 hours

A UK-based developer and pentester has claimed a $2,000 Bitcoin prize for demonstrating the exploitability of the PHP2Shell vulnerabilities that melted the internet last week.

Jaydip Modhwadia, 26, otherwise known as “Killa,” claimed the prize set by James Pavur, who launched the "Steal My Bitcoin" site on October 24.

Pavur launched the CTF (capture the flag) challenge to prove that the PHP2Shell exploit was not as easy as those in the cybersecurity community claimed it to be, promising to award $2,000 in Bitcoin to anyone who could achieve Remote Code Execution (RCE) on his website.

"My Bitcoin was stolen after 19.28 hours," the website now says, after Modhwadia claimed the prize, although the real time taken is thought to be less than three hours. 

Soon after Pavur launched the CTF on Saturday, prospective flag-catchers complained that the website he set up, which served only static HTML, was not built in a way that allowed the PHP2Shell exploit to achieve RCE.

The web page was running a vulnerable version of PHP, but the exploit path required a vulnerable website to serve a PHP file for flag-catchers to use as a hook – something that Pavur seemingly updated at around 1300 UTC on October 25.