Microsoft · Security update · September 8, 2026
KB5126104: September 2026 security update
KB5126104, released September 8, 2026, fixes 5 CVEs across 4 products. None of them is reported as exploited. Patch Radar priority: High.
High
CVEs closed
5
None rated Critical
Exploited
0
None reported
Exploitation more likely
0
Microsoft's assessment
Highest EPSS
0.0086
58th percentile
Priority of the 5 CVEs
Patch now 0
Urgent 0
High 4
Routine 1
Applies to
| Product |
|---|
| .NET 8.0 runtime installed on Linux |
| .NET 8.0 runtime installed on Mac OS |
| .NET 8.0 runtime installed on Windows |
| ASP.NET Core 8.0 |
CVEs this fix closes
| Priority | CVE | Component | Impact | CVSS | EPSS | Exploitation |
|---|---|---|---|---|---|---|
| High | CVE-2026-69522 | Visual Studio | Remote Code Execution | 8.8 | 0.0084 | Exploitation Unlikely |
| High | CVE-2026-69439 | .NET and Visual Studio | Elevation of Privilege | 8.8 | 0.0082 | Exploitation Unlikely |
| High | CVE-2026-71328 | Visual Studio | Remote Code Execution | 8.8 | 0.0082 | Exploitation Unlikely |
| High | CVE-2026-58649 | .NET | Information Disclosure | 7.0 | 0.0036 | Exploitation Less Likely |
| Routine | CVE-2026-69304 | ASP.NET Core | Denial of Service | 5.9 | 0.0086 | Exploitation Less Likely |
Showing 1 to 5 of 5
1
Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.