The PHP Meltdown Shows How AI Makes Bugs More Exploitable

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As security teams and web admins scrambled this week to patch newly public PHP bugs, criminal hackers quickly attempted to exploit the flaws in the wild. Millions of exploitation attempts hit within hours of the vulnerabilities being published, according to analysis from Cloudflare—unsurprising given broad access to AI tools that can make it easier for attackers to quickly exploit flaws.

So far, the nightmare scenario of mass victim takeovers and breaches hasn’t come to pass. The PHP Foundation says it hasn’t seen any successful exploitation of the bugs, collectively dubbed PHP2Shell, and many publicly circulating potential exploits appear to be ineffective. However, perhaps the most interesting role of AI amid the chaos this week is how advanced models helped researchers uncover practical exploitations for the vulnerabilities, which were known about, at least in part, for years. In other words, AI helped turn historic vulnerability into a current crisis.

So are we all about to be walloped by a wave of critical vulnerabilities that have been kicking around for decades?

Researchers at security company Calif were the first to identify the PHP2Shell vulnerabilities and create exploits in early August—partially using frontier AI tools as part of OpenAI’s Patch the Planet program, but also using expert human knowledge of PHP, its dynamics, and its weaknesses. Some of the underlying issues were identified in 2024 but were deemed too complex to exploit at the time. Following Calif’s discovery, researchers at OpenAI and the Google-owned security firm Wiz independently discovered PHP2Shell flaws using AI tools.

“The vulnerability had been known to the PHP team for years, but because it could not be leveraged by an attacker—at least, not a human one—it was not addressed,” says Sagi Tzadik, a security researcher at Wiz.

No software is perfect. There are inevitably flaws in even the most critical, foundational digital tools, but the expanding capabilities of AI models have made it faster to analyze and potentially exploit vulnerabilities. This puts even more pressure on under-resourced IT teams, developers, and admins to keep up. Microsoft’s security updates included a record 1,453 security vulnerabilities this month alone. Meanwhile, Bank of America recently hired 1,000 consultants to fix flaws discovered by Anthropic’s Mythos. Security researchers emphasize, though, that AI is ultimately not doing anything new, but rather magnifying existing dynamics of vulnerability discovery and coordinated disclosure.