CVE tracker / CVE-2026-62909
CVE-2026-62909
CVE-2026-62909 is the .NET Elevation of Privilege Vulnerability. Microsoft rates it Important, CVSS 7.8. It is not in CISA's Known Exploited Vulnerabilities catalog. Published August 11, 2026.
Risk summary
HighElevation of Privilege
7.8
CVSS v3 base
0.3%
EPSS: chance of exploitation in 30 days
High
Severity
Important
Microsoft's rating
Unlikely
Microsoft: exploitation
No
In CISA KEV
Microsoft describes it: “Uncaught exception in .NET allows an authorized attacker to elevate privileges locally.”
How to fix it
Microsoft lists 11 affected products and the update that fixes each:
- KB5122104 · fixed build 8.0.30
.NET 8.0 runtime installed on Linux, .NET 8.0 runtime installed on Mac OS, .NET 8.0 runtime installed on Windows - KB5122105 · fixed build 9.0.19
.NET 9.0 runtime installed on Linux, .NET 9.0 runtime installed on Windows, .NET 9.0 runtime installed on Mac OS - KB5122106 · fixed build 10.0.11
.NET 10.0 runtime installed on Linux, .NET 10.0 runtime installed on Windows, .NET 10.0 runtime installed on Mac OS - No update listed · fixed build 17.14.38
Microsoft Visual Studio 2022 version 17.14 - No update listed · fixed build 18.8.3
Microsoft Visual Studio 2026 version 18.8
What Microsoft changed
- August 11, 2026: Information published.
Details
- Weakness
- CWE-252: Unchecked Return Value
- Publicly disclosed (Microsoft)
- No
- Exploited (Microsoft)
- No
- Known exploited (CISA KEV)
- Not listed
- Published
- August 11, 2026
- Last revised
- August 11, 2026
Get told when this changes
Senserva Watch emails Microsoft security and patch alerts when something moves: a new exploitation report, a revised fix, a known issue. Free, one email address.
References
From Microsoft, CISA, NVD and FIRST data; the Microsoft details were read when this page was opened. Check the references above before you act.