Microsoft Patches Exploited SharePoint Zero-Day and 160 Other Vulnerabilities - SecurityWeek

Microsoft’s latest Patch Tuesday updates fix 165 vulnerabilities, including a SharePoint zero-day that has been exploited in the wild. The exploited SharePoint Server vulnerability is tracked as CVE-2026-32201 and it has been described as a spoofing issue. Microsoft assigned it an ‘important’ severity rating with a CVSS score of 6.5. “Improper input validation in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network,” Microsoft said, adding that an attacker may be able to exploit the flaw to access sensitive information and alter it. It’s unclear who is behind the zero-day attacks exploiting CVE-2026-32201 and what their motivation is. At the time of writing no information appears to be available and Microsoft has yet to say who reported the security hole. However, based on the vendor’s brief description it’s possible that CVE-2026-32201 is being chained with other weaknesses.  SharePoint vulnerabilities are often exploited in the wild. CISA’s Known Exploited Vulnerabilities (KEV) catalog currently includes 10 SharePoint flaws.  CVE-2026-32201 has already been added to CISA’s KEV list, and federal agencies have been instructed to patch it by April 28.  Of the remaining vulnerabilities patched by Microsoft with its April 2026 Patch Tuesday updates, 19 have an exploitability rating of ‘exploitation more likely’, which indicates that they may end up being exploited in attacks.   One of these vulnerabilities is CVE-2026-33825, a Microsoft Defender privilege-escalation issue that the tech giant says was publicly disclosed before patches were released. This is believed to be the vulnerability dubbed BlueHammer, which a disgruntled researcher recently made public. Security holes in Windows components such as Boot Loader, Active Directory, Remote Desktop, Hello, Storage Space Controllers, Search, TDI Translation Driver, BitLocker, Management Console, TCP/IP, Common Log File System Driver, UPnP Device Host, COM, Shell, Function Discovery Service, and Desktop Window Manager are also more likely to be exploited in the future. Satnam Narang, senior staff research engineer at Tenable, said this is the second-largest Patch Tuesday ever, just shy of the record set in October 2025. Adobe has patched more than 50 vulnerabilities across 11 products with its latest Patch Tuesday fixes. *updated to note that CVE-2026-33825 is believed to be the vulnerability dubbed BlueHammer. Related: SAP Patches Critical ABAP Vulnerability Related: Microsoft Patches 83 Vulnerabilities Related: Organizations Warned of Exploited Windows, Adobe Acrobat Vulnerabilities WRITTEN BY Eduard Kovacs Eduard Kovacs (@EduardKovacs) is senior managing editor at SecurityWeek. He worked as a high school IT teacher before starting a career in journalism in 2011. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering. More from Eduard Kovacs Firefox Vulnerability Allows Tor User Fingerprinting Locked Shields 2026: 41 Nations Strengthen Cyber Resilience in World’s Biggest Exercise Vulnerabilities Patched in CrowdStrike, Tenable Products Chinese Cybersecurity Firm’s AI Hacking Claims Draw Comparisons to Claude Mythos AI Can Autonomously Hack Cloud Systems With Minimal Oversight: Researchers  After Bluesky, Mastodon Targeted in DDoS Attack Claude Mythos Finds 271 Firefox Vulnerabilities Google Antigravity in Crosshairs of Security Researchers, Cybercriminals Latest News Medtronic Hack Confirmed After ShinyHunters Threatens Data Leak Incomplete Windows Patch Opens Door to Zero-Click Attacks OpenSSH Flaw Allowing Full Root Shell Access Lurked for 15 Years Malicious AI Prompt Injection Attacks Increasing, but Sophistication Still Low: Google Energy and Water Management Firm Itron Hacked UNC6692 Uses Email Bombing, Social Engineering to Deploy ‘Snow’ Malware Easily Exploitable ‘Pack2TheRoot’ Linux Vulnerability Leads to Root Access US Launches Sweeping Crackdown on Southeast Asia Cyberscams and Sanctions Cambodian Senator Trending Webinar: A Step-By-Step Approach To AI Governance April 28, 2026 With "Shadow AI" usage becoming prevalent in organizations, learn how to balance the need for rapid experimentation with the rigorous controls required for enterprise-grade deployment. Register Virtual Event: Threat Detection And Incident Response Summit May 20, 2026 Delve into big-picture strategies to reduce attack surfaces, improve patch management, conduct post-incident forensics, and tools and tricks needed in a modern organization. Register People on the Move Neill Feather has been named Chief Executive Officer at Point Wild. Oasis Security has appointed Michael DeCesare as President. Sterling Wilson has joined IGEL as Global Field CTO, Business Continuity and Disaster Recovery. More People On The Move Expert Insights Why Cybersecurity Must Rethink Defense In The Age Of Autonomous Agents From autonomous code generation to decision-making systems that initiate actions without human intervention, the industry is entering a new phase. (Torsten George) Government Can’t Win The Cyber War Without The Private Sector Securing national resilience now depends on faster, deeper partnerships with the private sector. (Steve Durbin) The Hidden ROI Of Visibility: Better Decisions, Better Behavior, Better Security Beyond monitoring and compliance, visibility acts as a powerful deterrent, shaping user behavior, improving collaboration, and enabling more accurate, data-driven security decisions. (Joshua Goldfarb) The New Rules Of Engagement: Matching Agentic Attack Speed The cybersecurity response to AI-enabled nation-state threats cannot be incremental. It must be architectural. (Nadir Izrael) The Next Cybersecurity Crisis Isn’t Breaches—It’s Data You Can’t Trust Data integrity shouldn’t be seen only through the prism of a technical concern but also as a leadership issue. (Steve Durbin) Flipboard Reddit Whatsapp Email