CVE-2026-21510 | Windows Shell Security Feature Bypass Vulnerability

CVE-2026-21510 is a security feature bypass vulnerability affecting Windows Shell. It was assigned a CVSSv3 score of 8.8 and was rated as important. According to Microsoft, this flaw was publicly disclosed prior to a patch being made available and was also exploited in the wild as a zero-day. Exploitation requires an attacker to convince an unsuspecting user to open a malicious link or shortcut file. This would allow the attacker to bypass Windows SmartScreen and Windows Shell warnings by exploiting a flaw in Windows Shell components.

CVE-2026-21533 | Windows Remote Desktop Services Elevation of Privilege Vulnerability

CVE-2026-21533 is an EoP vulnerability affecting Windows Remote Desktop Services. It was assigned a CVSSv3 score of 7.8, rated as important and was reportedly exploited in the wild. Successful exploitation allows a local, authenticated attacker to elevate to SYSTEM privileges.

CVE-2026-21519 | Desktop Window Manager Elevation of Privilege Vulnerability

CVE-2026-21519 is an EoP vulnerability affecting Desktop Window Manager, a Windows service used to render the graphical user interface (GUI) in Windows. It was assigned a CVSSv3 score of 7.8 and rated as important. A local, authenticated attacker could exploit this vulnerability to elevate to SYSTEM privileges. According to Microsoft, this vulnerability was exploited in the wild as a zero-day.

CVE-2026-21514 | Microsoft Word Security Feature Bypass Vulnerability

CVE-2026-21514 is a security feature bypass vulnerability affecting Microsoft Word. It was assigned a CVSSv3 score of 7.8 and rated as important. Successful exploitation requires an attacker to convince a user to open a crafted Office file. According to the Microsoft advisory, the preview pane is not an attack vector. This vulnerability was publicly disclosed prior to a patch being made available and was also exploited in the wild as a zero-day. Microsoft credited the discovery of this vulnerability to an Anonymous researcher, Google Threat Intelligence Group, Microsoft Threat Intelligence Center (MSTIC), Microsoft Security Response Center (MSRC) and Office Product Group Security Team.

CVE-2026-21525 | Windows Remote Access Connection Manager Denial of Service Vulnerability

CVE-2026-21525 is a denial of service (DoS) vulnerability affecting Windows Remote Access Connection Manager (also known as RasMan), a tool used for the management of multiple remote desktop connections. It was assigned a CVSSv3 score of 6.2, was rated as important and was exploited in the wild. While no information has been released about the exploitation of this DoS, the advisory credits the 0patch vulnerability research team for reporting this flaw.

CVE-2026-21513 | MSHTML Framework Security Feature Bypass Vulnerability

CVE-2026-21513 is a security feature bypass vulnerability in the MSHTML Framework. It was assigned a CVSSv3 score of 8.8 and rated as important. According to Microsoft, it was both exploited in the wild and publicly disclosed prior to a patch being available. Successful exploitation of this flaw requires an attacker to convince a potential victim into opening either a malicious HTML file or a shortcut (.lnk) file. Like similar security feature bypass flaws, this vulnerability can bypass protection prompts that would caution a user before opening a file.

CVE-2026-21511 | Microsoft Outlook Spoofing Vulnerability

CVE-2026-21511 is a spoofing vulnerability affecting Microsoft Outlook. It was assigned a CVSSv3 score of 7.5 and was rated as important. The spoofing vulnerability is the result of a deserialization of untrusted data flaw, which an attacker can trigger using a crafted email. Microsoft notes that the preview pane is an attack vector for this flaw. CVE-2026-21511 was assessed as “Exploitation More Likely” according to Microsoft’s Exploitability Index.

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