I want my Wednesday back

The recent buzz surrounding the php2shell exploit may have raised concerns among website owners, but the reality is far more nuanced. The PoC (Proof of Concept) for php2shell presented is not as straightforward as it appears, and mass exploitation is not imminent.

To exploit the vulnerability, an attacker would need to make four consecutive requests to the same php worker process, knowing the exact php build configuration, which includes the version, operating system, and architecture. This is a challenging task, as php builds vary widely.

Even if an attacker were to utilize a docker image with the default number of workers (150) and open a large number of connections to keep other workers occupied, they would still need to try a vast number of combinations. Assuming they focus on the 50 most popular php/OS combinations and attempt exploits for worker counts ranging from 10 to 1010, they would face over 50,000 attempts.

However, this brute force approach would be akin to a denial-of-service (DoS) attack, taking several days of continuous effort. Moreover, the PoC's execution time of 3-4 seconds on localhost translates to approximately 10 seconds on the internet. This rate, combined with constant background traffic, makes mass exploitation highly impractical.

The attack would also be vulnerable to detection through rate-limiting or IP blocking, especially on high-traffic websites that already employ these defenses. Furthermore, running the attack from multiple IP addresses could increase the likelihood of timing errors, further reducing the chances of success.

While the php2shell vulnerability is indeed critical and merits attention, the claims of immediate, mass exploitation within 15 minutes are overly dramatic. Website owners should prioritize patching promptly, particularly if they operate low-traffic sites with minimal bot protection. However, it is essential to temper expectations and avoid exaggerated statements about the exploit's potential impact.