
The vulnpocalypse has begun. Palo Alto Networks usually finds five vulnerabilities a month, but on Wednesday said it scanned its entire codecase using the latest frontier models, including Anthropic's Mythos, and found 75 security holes, covered in 26 CVEs. This comes a day after Microsoft said it used its new agentic bug hunting system called MDASH to find 17 vulnerabilities across its products - on a record-setting Patch Tuesday that saw Redmond disclose a whopping 30 critical CVEs. Plus, last week Mozilla said it fixed 423 Firefox bugs in April, which is more than five times higher than the 76 fixes issued in March and almost 20 times higher than its 21.5 monthly average last year. The browser maker previously said Mythos found 271 flaws in Firefox 150. It shouldn't be all that shocking. Security vendors have long warned about attackers using AI, and how this means defenders need to operate at AI speed to protect their own networks and systems (aka buying their AI-infused products). Now that models have become really good at finding bugs in code, security shops are using AI to scan their own software, hopefully to uncover and fix flaws before the baddies do. And this trickles down to two things: more patches, and more work for admins. Zero Day Initiative's chief vuln finder Dustin Childs agrees with this assessment. At first, yes, this means more patches and thus more work for admins," he told The Register. The goal over time would be to eliminate as many as possible, and, over time, that monthly number goes down." What will make this whole AI bug hunting season really painful," he continued, is if the patches don't work or - worse yet - break things. Many customers don't trust patches as it is, so if AI-related patches break things, they are less likely to apply as time goes on," Childs added. This will be true even if AI only finds the bugs and doesn't make the patches." Bug hunting on steroids This isn't to say security companies should avoid AI to find and fix flaws. All vendors should use what tools they have to find and remediate bugs before they are exploited in the wild," Childs said. Ideally, they would find the bugs before they even ship, but I'm not holding my breath for that to happen." Both Microsoft and Palo Alto Networks (PAN) are part of Anthropic's Project Glasswing, which means they are among the select group of entities allowed to test Mythos, the much-hyped LLM, to find security holes in their own products. Palo Alto Networks began testing Mythos on April 7, and has since continued using the LLM and other frontier models, including Claude Opus 4.7 and OpenAI's GPT-5.5-Cyber, according to product manager Lee Klarich. Today, we released our May Patch Wednesday' security advisories," Klarich said in a Wednesday blog, adding that this is the first time where the majority of findings were the result of frontier AI models scanning our code." The LLMs scanned over 130 Palo Alto Networks products and platforms platforms, and as noted above found 75 issues, covered in 26 CVEs. None of these bugs are under exploitation, and as of Wednesday the company has fixed all bugs in its SaaS-delivered products and coded patches for all customer-operated products. Maybe 5 months before 'AI-driven exploits the new norm' We intend to fix every vulnerability we find before advanced AI capabilities become widely available to adversaries," Klarich said in his blog, adding that his company expects a narrow three-to-five-month window for organizations to outpace the adversary before AI-driven exploits start to become the new norm." A day earlier, Microsoft said its new multi-model agentic scanning harness (codename MDASH) helped researchers find 16 new vulnerabilities across the Windows networking and authentication stack, as disclosed in May's Patch Tuesday event. This included four critical remote code execution flaws in components such as the Windows kernel TCP/IP stack and the IKEv2 service. Unlike single-model approaches, the harness orchestrates more than 100 specialized AI agents across an ensemble of frontier and distilled models to discover, debate, and prove exploitable bugs end-to-end," Microsoft VP of agentic security Taesoo Kim said in a Tuesday blog. Tom Gallagher, VP of engineering at Microsoft Security Response Center, admitted that this month's release sits on the larger side of a hotpatch month." Gallagher said he expects AI-assisted bug hunting to increase Patch Tuesday releases as both Microsoft and third-party researchers use these tools to boost vulnerability discovery. And yes, all of this ultimately means more patches and more work. More patches = more work Finding bugs has always been the cheap end of the pipeline," Luta CEO Katie Moussouris told The Register. Triage, disclosure, building patches that do not break production, and getting customers to deploy them is the expensive end, and nobody has funded it for this volume." Moussouris helped convince Redmond's top brass that Microsoft needed a bug bounty program in 2013, and three years later started her own bug bounty consultancy. She noted Palo Alto Networks' staggering jump in CVEs this month. Multiply that across every vendor and the bottleneck becomes admins and vulnerability management teams," Moussouris said. And she also stressed that people should be using these new models to find vulnerabilities. It is exactly what defenders should be doing," Moussouris said. Both PAN and Microsoft landed on the same answer: no single model catches everything. PAN ran Claude Mythos, Claude Opus 4.7, and GPT-5.5-Cyber because each finds bugs the others miss," she added. Microsoft orchestrates over 100 specialized agents across multiple models. Add threat intel and codebase context, and Microsoft rediscovered 96 percent of five years of confirmed bugs in a critical Windows component. The asymmetry is temporary, PAN puts adversary parity at three to five months, so any vendor not scanning their own code now is letting someone else find their bugs first."(R)