Microsoft cuts off China's early access to bug disclosures
theregister.com 21.08.2025 - Better late than never after SharePoint assault? Microsoft has reportedly stopped giving Chinese companies proof-of-concept exploit code for soon-to-be-disclosed vulnerabilities following last month's SharePoint zero-day attacks, which appear to be related to a leak in Redmond's early-bug-notification program. The software behemoth gives some software vendors early bug disclosures under its Microsoft Active Protections Program (MAPP), which typically delivers info two weeks before Patch Tuesday. MAPP participants sign a non-disclosure agreement, and in exchange get vulnerability details so that they can provide updated protections to customers more quickly. According to Microsoft spokesperson David Cuddy, who spoke with Bloomberg about changes to the program, MAPP has begun limiting access to companies in "countries where they're required to report vulnerabilities to their governments," including China. Companies in these countries will no longer receive "proof of concept" exploit code, but instead will see "a more general written description" that Microsoft sends at the same time as patches, Cuddy told the news outlet. Microsoft did not respond to The Register's inquiries. In late July, China-based crews – including government goons, data thieves, and a ransomware gang – exploited a couple of bugs that allowed them to hijack on-premises SharePoint servers belonging to more than 400 organizations and remotely execute code. Redmond disclosed the two SharePoint flaws during its July 8 Patch Tuesday event, and a couple weeks later admitted that the software update didn't fully fix the issues. The Windows giant issued working patches on July 21 to address its earlier flawed fixes, but by then the bugs were already under mass exploitation. This led some to speculate that whomever was exploiting the CVEs knew about them in advance – and also knew how to bypass the original patches. "A leak happened here somewhere," Dustin Childs, head of threat awareness at Trend Micro's Zero Day Initiative (ZDI), told The Register in July. "And now you've got a zero-day exploit in the wild, and worse than that, you've got a zero-day exploit in the wild that bypasses the patch, which came out the next day." One possible explanation: Someone leaked details from the MAPP update to Beijing. Childs said ZDI was able to poke holes in the initial patches. China does not lack talented security researchers capable of doing likewise. At the time, Microsoft declined to answer The Register's specific questions about what role, if any, MAPP played in the SharePoint attacks. "As part of our standard process, we'll review this incident, find areas to improve, and apply those improvements broadly," a Microsoft spokesperson told us in July. Microsoft today declined to comment on its internal investigation. Childs today told The Register that the MAPP change "is a positive change, if a bit late. Anything Microsoft can do to help prevent leaks while still offering MAPP guidance is welcome." "In the past, MAPP leaks were associated with companies out of China, so restricting information from flowing to these companies should help," Childs said. "The MAPP program remains a valuable resource for network defenders. Hopefully, Microsoft can squelch the leaks while sending out the needed information to companies that have proven their ability (and desire) to protect end users."
