CVE-2026-58649

mediumpriority · track · 26EPSS 0.004 · 30 %ileDENLUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.36% (30th) EPSS

CVSS 6.5 · medium

Is it mine?

73 products

Check your exposure

Who says so?

3 sources

cert_bund · ncsc_nl · msrc_csaf

EPSS · scored 2026-10-27

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

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixed.NET 10.0 installed on Linuxmsrc_csaf
10.0.111, 10.0.400:Security Update:https://support.microsoft.com/help/5126106
https://support.microsoft.com/help/5126106
Fixed.NET 10.0 installed on Mac OSmsrc_csaf
10.0.111, 10.0.400:Security Update:https://support.microsoft.com/help/5126106
https://support.microsoft.com/help/5126106
Fixed.NET 10.0 installed on Windowsmsrc_csaf
10.0.111, 10.0.400:Security Update:https://support.microsoft.com/help/5126106
https://support.microsoft.com/help/5126106
Fixed.NET 11.0 installed on Linuxmsrc_csaf
11.0 RC1:Security Update
Fixed.NET 11.0 installed on Mac OSmsrc_csaf
11.0 RC1:Security Update
Fixed.NET 11.0 installed on Windowsmsrc_csaf
11.0 RC1:Security Update
Fixed.NET 8.0 installed on Linuxmsrc_csaf
8.0.130, 8.0.424:Security Update:https://support.microsoft.com/help/5126104
https://support.microsoft.com/help/5126104
Fixed.NET 8.0 installed on Mac OSmsrc_csaf
8.0.130, 8.0.424:Security Update:https://support.microsoft.com/help/5126104
https://support.microsoft.com/help/5126104
Fixed.NET 8.0 installed on Windowsmsrc_csaf
8.0.130, 8.0.424:Security Update:https://support.microsoft.com/help/5126104
https://support.microsoft.com/help/5126104
Fixed.NET 9.0 installed on Linuxmsrc_csaf
9.0.120, 9.0.317:Security Update:https://support.microsoft.com/help/5126105
https://support.microsoft.com/help/5126105
Fixed.NET 9.0 installed on Mac OSmsrc_csaf
9.0.120, 9.0.317:Security Update:https://support.microsoft.com/help/5126105
https://support.microsoft.com/help/5126105
Fixed.NET 9.0 installed on Windowsmsrc_csaf
9.0.120, 9.0.317:Security Update:https://support.microsoft.com/help/5126105
https://support.microsoft.com/help/5126105
FixedMicrosoft Visual Studio 2022 version 17.14msrc_csaf
17.14.40:Security Update:https://learn.microsoft.com/en-us/visualstudio/releases/2022/release-notes
https://learn.microsoft.com/en-us/visualstudio/releases/2022/release-notes
FixedMicrosoft Visual Studio 2026 version 18.9msrc_csaf
18.9.3:Security Update:https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes
https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:Nprimary · secure@microsoft.com USexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-346USCWE-346US

affected products (73)

Products and version ranges known to be affected.

Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Microsoft .NET 10.0all versionscert_bundDEcpe:/a:microsoft:.net:10.0
Microsoft .NET 11.0all versionscert_bundDEcpe:/a:microsoft:.net:11.0
Microsoft .NET 8.0all versionscert_bundDEcpe:/a:microsoft:.net:8.0
Microsoft .NET 9.0all versionscert_bundDEcpe:/a:microsoft:.net:9.0
Microsoft .NET Framework 3.5all versionscert_bundDEcpe:/a:microsoft:.net_framework:3.5
Microsoft .NET Framework 4.6.2all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.6.2
Microsoft .NET Framework 4.7all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.7
Microsoft .NET Framework 4.7.1all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.7.1
Microsoft .NET Framework 4.7.2all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.7.2
Microsoft .NET Framework 4.8.1all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.8.1
Microsoft ASP.NET Core 10.0all versionscert_bundDEcpe:/a:microsoft:asp.net:core_10.0
Microsoft ASP.NET Core 8.0all versionscert_bundDEcpe:/a:microsoft:asp.net:core_3.1
Microsoft ASP.NET Core 8.0all versionscert_bundDEcpe:/a:microsoft:asp.net:core_8.0
Microsoft ASP.NET Core 9.0all versionscert_bundDEcpe:/a:microsoft:asp.net:core_9.0
Microsoft Visual Studio Codeall versionscert_bundDEcpe:/a:microsoft:visual_studio_code:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-

showing 20 of 73

advisories (3)

Vendor and ecosystem advisories describing this.

NCSC-2026-0351Kwetsbaarheden verholpen in Microsoft Developer ToolsNL2026-09-08csaf · ncsc_nlNL
Microsoft heeft 15 kwetsbaarheden verholpen in diverse Developer Tools.
WID-SEC-W-2026-3242Microsoft Entwicklerwerkzeuge: Mehrere Schwachstellen ermöglichen PrivilegieneskalationDeutsch2026-09-08csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in verschiedenen Microsoft Entwicklerwerkzeugen ausnutzen, um seine Privilegien zu erhöhen, um Sicherheitsmechanismen zu umgehen, sowie Informationen zu manipulieren oder offenzulegen.
msrc_CVE-2026-58649.NET Information Disclosure Vulnerability2026-09-08csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

sources

Which sources assert this record, and when.

cert_bund ncsc_nl msrc_csaf NVD CVE.org MITRE

published 2026-09-08modified 2026-10-07

references (1) nvd

External citations — patches, advisories, analysis.

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58649PatchVendor Advisory

scry

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