Nightmare Eclipse, the prolific zero-day vulnerability hunter with an axe to grind against Microsoft, released yet another exploit late Wednesday that the researcher claims will spawn a command prompt that provides total access to the BitLocker volume. This bug, called GreatXML, was “an accidental discovery,” according to the researcher, who said it only took four hours to find. They claim this exploit (published on GitHub and Git-based code-hosting platforms) can bypass BitLocker on any system that has ever run a Microsoft Defender Offline scan at any point in the past. GreatXML comes just a day after Nightmare released exploit code for RoguePlanet, which allows local privilege escalation and leads to SYSTEM-level control over an affected machine. This brings the researcher’s zero-day count to eight. The earlier six - RedSun, UnDefend, BlueHammer, YellowKey, GreenPlasma, and MiniPlasma - all have patches as of this week’s Patch Tuesday event. Redmond on Wednesday told The Register that it is aware of RoguePlanet, and “actively investigating the validity and potential applicability of these claims.” The Windows giant didn’t immediately respond to our inquiries about GreatXML, including when it planned to issue a patch. Microsoft has said none of the vulnerabilities were reported via its official channels prior to being made public. The company also banned Nightmare’s earlier GitHub account, and seemingly threatened legal action before dialing back its rhetoric after steep backlash from the security community. Nightmare Eclipse, who some researchers suggest is an ex-Microsoft employee, harbors a very personal grudge against the Windows giant and its communications with bug hunters. They have promised to keep the zero-days coming, but waffle on the timing. Last month, the researcher pledged a big July 14 drop: “I will make sure your bones are shattered that day,” and then added, “nothing will be released this June (or maybe I will release smtg, depending on circumstances).” On Tuesday, they changed course. “I will be unable to mass disclose zerodays in July 14th, RoguePlanet took way more time than expected and truly drained me. I might take a break but I can't say for sure what I will be doing for next month, maybe it's nothing, maybe it's smtg.” A day later, Nightmare released the “accidental” GreatXML BitLocker bypass. According to the researcher, the BitLocker bypass first requires copying “unattend.xml” and the “Recovery” directory to the root of the recovery partition. The next step is rebooting into WinRE by Shift-clicking Restart. “If everything was done correctly, a shell with unrestricted access to the bitlocker volume will spawn,” Nightmare wrote. Also, if the scan hasn’t even been initiated on the Windows system, first you’d need to either log in and initiate it, or “figure out a way to boot into WinRE in offline scan state.” Security sleuth Will Dormann followed Nightmare’s steps to reproduce GreatXML, and said the writeup seems “flawed.” In his testing, Dormann said the command prompt appeared the next time a Defender Offline scan ran. “And in order to trigger a Microsoft Defender Offline scan, you both need to be logged in to Windows, and also have admin credentials,” he wrote on social media. “And if you've already got that level of access, you can just turn off bitlocker.” “The writeup for GreatXML suggests that the prerequisite is that Windows Defender Offline has been executed at some point in the past,” Dormann added. “And that after planting two files in WinRE, all you need to do is [Shift]-reboot into WinRE, and Windows will automatically go into Microsoft Defender Offline scan mode. But this is not the case in any of the 3 lineages of Win11 that I have handy.” ®

UPDATED Following notes from several readers, we followed up directly with VRChat on Thursday at 1945 GMT and they told us that the Maine Attorney General's office apparently posted a fake breach report. According to an email from VRChat's head of community, Charles Tupper, "VRChat did not submit this Notice of Data Incident, and the employee/email cited does not exist. We have no reason to believe that our data or systems have been compromised. We are in the process of contacting the Maine Attorney General's office to have this removed." In an effort to get to the bottom of this, The Register dialed the phone number on the report as well, but it connected to a line that is not in service. We also tried emailing the address on the report and got no reply. We could find no record of a Scott Caruso affiliated with VRChat. We apologize for the error, but generally speaking, government data breach reports are considered reliable. The fakers apparently even created a false notice that VRChat ostensibly sent to customers! If anybody knows who filed this apparently fake report and why, get in touch through our contact page, or through our secure tipline. The original story is below: Online chat platform VRChat says a recent cyberattack compromised the data belonging to nearly 2.5 million users. It confirmed the “data security incident” in a report filed with Maine’s attorney general, but has not disclosed it via public channels. The company’s report confirmed that its cloud environment was accessed between May 10-12, with the unauthorized intruder making off with information concerning 2,436,782 users. This included VRChat usernames, email addresses, whether a user was a VRChat+ subscriber, login histories (including device, hardware identifiers, and IP addresses), and Steam or Meta user IDs. It does not believe passwords, credit cards or other payment information, or government IDs used for age verification were affected. “VRChat sincerely regrets that this security incident occurred,” the company stated in its disclosure. “We understand that trust between our platform and its community is earned through consistent action, and we take full responsibility for the concern this event has caused. “The security and privacy of our players' information remain our highest priority, and we are committed to doing everything within our power to protect it.” VRChat said that after it was made aware of the intrusion, it contained the threat and implemented additional security controls, as well as engaging outside security experts. And in an unusual move for US breaches, the San Francisco-based company did not offer identity theft or credit monitoring services. Offering these kinds of services is not a legal requirement, but doing so is highly common, especially regarding attacks that affect so many individuals. VRChat does not publish the total number of registered users that it has on its books, but its documentation states that “the platform has grown to millions of users,” who have collectively published tens of millions of unique pieces of content for it since its first release in 2014. The part game, part chat platform is an online, open-world chatroom where people walk around interacting with one another via their 3D avatars. It has been compared to Second Life in that users explore other users' worlds, play mini-games, and partake in casual chit-chat, with support for both virtual reality headsets and conventional PCs. You can also think of it as something similar to Meta’s vision for the metaverse, just without all the coworking and KPI meetings, and with way more users. ®