Patch Actively Exploited Flaws in SharePoint and Winsock
NEOSEC enrichment — no mirror of the original source
Three Microsoft flaws are under recent active exploitation. CVE-2026-55040, CVSS score 9.1, allows an unauthorized attacker to bypass a security feature over a network due to weak authentication in SharePoint. This vulnerability was patched
Source: SANS NewsBites. For licensing reasons NEOSEC Intel does not mirror the full text verbatim. The full text and expert commentary are available at the original source.
Editorial context in the original issue
The SANS NewsBites issue carries commentary by: Dukes, Neely, Skoudis.
Linked advisories
- CVE-2026-55040Microsoft SharePoint Server Security Feature Bypass Vulnerability
- CVE-2026-45659Security Advisory 2026-009 — Critical Vulnerabilities in Microsoft SharePoint
- CVE-2026-45659Microsoft SharePoint Enterprise Server 2016: Deserialisierung nicht vertrauenswürdiger Daten
- CVE-2026-45659Microsoft SharePoint Server — Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
- CVE-2026-68820Microsoft Windows Ancillary Function Driver for WinSock — Microsoft Windows Ancillary Function Driver for WinSock Use-After-Free Vulnerability
- CVE-2026-45659Microsoft SharePoint Server 2016 und SharePoint Server 2019: Schwachstelle ermöglicht Codeausführung
- CVE-2026-68820microsoft windows_10_1607: Use-After-Free
- CVE-2026-55040Microsoft SharePoint Enterprise Server 2016: Umgehung einer Sicherheitsfunktion
- CVE-2026-68820Microsoft Windows Produkte: Mehrere Schwachstellen
- CVE-2026-55040Microsoft Office Produkte: Mehrere Schwachstellen
- CVE-2026-45659Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.
- CVE-2026-45659Microsoft SharePoint Remote Code Execution Vulnerability
- CVE-2026-68820Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
- CVE-2026-55040Microsoft SharePoint — Microsoft SharePoint Weak Authentication Vulnerability
Affected vendors and products
- Microsoft Microsoft Sharepoint Enterprise Server 2016
- Microsoft Microsoft Sharepoint Server 2019
- Microsoft Microsoft Sharepoint Server Subscription Edition
- Microsoft Microsoft SharePoint Server Subscription Edition
- Microsoft Sharepoint Server 2019
- Microsoft Microsoft Windows 10 1607
- Microsoft Microsoft Windows 10 1809
- Microsoft Microsoft Windows 10 21H2
- Microsoft Microsoft Windows 10 22h2
- Microsoft Windows 10 Version 1607
- Microsoft Windows 10 Version 1809
- Microsoft Windows 10 Version 21h2
More on SharePoint
Other advisories
- HighCVE-2026-108452Eine unzureichende Einschränkung eines Pfadnamens auf ein eingeschränktes Verzeichnis (Pfad-Traversierung) in Microsoft Office SharePoint er...
- HighCVE-2026-108452Microsoft SharePoint Server Subscription Edition: Pfadüberschreitung (Path Traversal)
- HighCVE-2026-108452Microsoft Office SharePoint Remote Code Execution Vulnerability
- HighCVE-2026-88164Fehlende Zugriffskontrolle in Microsoft Office SharePoint ermöglicht es einem authentifizierten Angreifer, seine Rechte über ein Netzwerk auszuweiten.
- HighCVE-2026-88164Fehlende Zugriffskontrolle in Microsoft Office SharePoint ermöglicht es einem authentifizierten Angreifer, seine Rechte über ein Netzwerk auszuweiten.
- HighCVE-2026-105013Die Deserialisierung von nicht vertrauenswürdigen Daten in Microsoft Office SharePoint ermöglicht es einem autorisierten Angreifer, Code über ein Netzwerk auszuführen.
- HighCVE-2026-105013Die Deserialisierung von nicht vertrauenswürdigen Daten in Microsoft Office SharePoint ermöglicht es einem autorisierten Angreifer, Code über ein Netzwerk auszuführen.
- HighCVE-2026-96044In Microsoft Office SharePoint ermöglicht eine Schwachstelle einem autorisierten Angreifer die Rechteausweitung über ein Netzwerk.
Other news entries
- Microsoft Patches Record 1,413 Flaws, Including Exploited Windows Shell BugNewsThe Hacker News
- NCSC-2026-0422 [1.00] [M/H] Kwetsbaarheden verholpen in Microsoft OfficeNewsNCSC-NL
- Warlock Exploits SharePoint Flaws to Disable Security Tools and Deploy RansomwareNewsThe Hacker News
- Warlock ransomware breach SharePoint in water, telecom operator attacksNewsBleepingComputer
- Warlock Expands SharePoint Exploitation in Critical Infrastructure AttacksNewsSecurityWeek
- Microsoft SharePoint Flaw CVE-2026-65660 Now Exploited in AttacksNewsSecurityWeek
- SharePoint RCE and MikroTik RouterOS Flaws Actively Exploited in the WildNewsThe Hacker News
- CISA warns of Sharepoint, WSO2, Adobe Commerce flaws exploited in attacksNewsBleepingComputer
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