Microsoft .NET Framework, SharePoint, and Visual Studio Remote Code Execution Vulnerability
A remote code execution vulnerability exists in .NET Framework, Microsoft SharePoint, and Visual Studio when the software fails to check the source markup of XML file input, aka '.NET Framework, SharePoint Server, and Visual Studio Remote…
Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.
Exploitation probability EPSS · FIRST
Exploitation signals 3 / 5
- KEV catalog (CISA)03 Nov 2021
- Exploited in EUVD (ENISA)03 Nov 2021
- Used by ransomwareno
- EPSS above 10 %95.8%
- No account, over the networkno
What to do
Fix
Update to a fixed version: 3.1.6
CISA guidance: Apply updates per vendor instructions.
Meanwhile
Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.
Manufacturers (CRA)
Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained
Description ENISA EUVD
A remote code execution vulnerability exists in .NET Framework, Microsoft SharePoint, and Visual Studio when the software fails to check the source markup of XML file input, aka '.NET Framework, SharePoint Server, and Visual Studio Remote Code Execution Vulnerability'.
Affected products
- 16.0
- unspecified
- Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
- Windows Server 2012 R2
- Windows RT 8.1
- 2019
- Windows Server 2012 R2 (Server Core installation)
- Windows Server 2012
- Windows Server 2008 R2 for x64-based Systems Service Pack 1
- Windows 8.1 for x64-based systems
- Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2
- 2013 Service Pack 1
Open source packages OSV
- Microsoft.NETCore.App.Runtime.linux-x64NuGet · GHSA-g5vf-38cp-4px9fixed in 3.1.6
Timeline
-
Published
-
Exploitation reported (ENISA)
-
Added to the KEV catalog
-
CISA remediation due date
-
EPSS peak: 95.8%
References
Other exploited vulnerabilities from the same vendor
- CVE-2026-96951Microsoft Windows Command Injection Vulnerability5.6 · Actively exploited
- CVE-2026-65660Microsoft SharePoint Code Injection Vulnerability5.0 · Actively exploited
- CVE-2026-85880Microsoft Windows Heap-Based Buffer Overflow Vulnerability4.3 · Actively exploited
- CVE-2026-81963Microsoft Windows Link Following Vulnerability4.3 · Actively exploited
- CVE-2019-1068Microsoft SQL Server Remote Code Execution Vulnerability7.0 · Actively exploited
- CVE-2026-69836Microsoft Entra5.3 · Actively exploited