CVE-2026-58649: .NET Information Disclosure Vulnerability

Published Sep 8, 2026
·
Updated

.NET Information Disclosure Vulnerability

Other sources

Origin validation error in .NET allows an unauthorized attacker to disclose information over a network.

Microsoft

Affected Software

14 affected componentsFixes available
Microsoft Visual Studio 2026=18.9
18.9.3
Microsoft .NET 9.0 installed on Linux<9.0.120, 9.0.317
9.0.120, 9.0.317
Microsoft .NET 10.0 installed on Linux<10.0.111, 10.0.400
10.0.111, 10.0.400
Microsoft .NET 10.0 installed on Windows<10.0.111, 10.0.400
10.0.111, 10.0.400
Microsoft .NET 10.0 installed on Mac OS<10.0.111, 10.0.400
10.0.111, 10.0.400
Microsoft .NET 9.0 installed on Mac OS<9.0.120, 9.0.317
9.0.120, 9.0.317
Microsoft .NET 9.0 installed on Windows<9.0.120, 9.0.317
9.0.120, 9.0.317
Microsoft .NET 11.0 installed on Windows<11.0 RC1
11.0 RC1
Microsoft .NET 8.0 installed on Linux<8.0.130, 8.0.424
8.0.130, 8.0.424
Microsoft .NET 8.0 installed on Mac OS<8.0.130, 8.0.424
8.0.130, 8.0.424
Microsoft .NET 8.0 installed on Windows<8.0.130, 8.0.424
8.0.130, 8.0.424
Microsoft .NET 11.0 installed on Mac OS<11.0 RC1
11.0 RC1
Microsoft .NET 11.0 installed on Linux<11.0 RC1
11.0 RC1
Microsoft Visual Studio 2022=17.14
17.14.40

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.111, 10.0.400
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 9.0.120, 9.0.317
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 18.9.3
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 11.0 RC1
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.0.130, 8.0.424
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 17.14.40

Event History

Sep 8, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:17 PM
Data Sourced
via MITRE·05:17 PM
DescriptionSeverity
Data Sourced
via NVD·06:17 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What access does an attacker need to exploit this issue?

The attacker can attempt exploitation over a network without prior privileges, but user interaction is required.

2

Which environments are identified as affected?

The listed affected software includes Microsoft Visual Studio 2026 and Microsoft .NET 9.0, 10.0, and 11.0 installations across Linux, Windows, and macOS, with .NET 11.0 specifically listed for Windows.

Contact

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