CVE-2026-23666

highpriority · track · 0EPSS 0.013 · 71 %ileDEEUJPNLRUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.33% (71st) EPSS

CVSS 7.5 · high

Is it mine?

156 products

Check your exposure

Who says so?

7 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-23

Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.

remediations

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

A vendor fix is available.

FixedMicrosoft .NET Framework 3.5msrc_csaf
2.0.50727.8982 & 3.0.30729.8976:Security Update:https://support.microsoft.com/help/5082398
https://support.microsoft.com/help/5082398
FixedMicrosoft .NET Framework 3.5 AND 4.7.2msrc_csaf
2.0.50727.9068 & 3.0.30729.9065 & 4.7.4141.0:Security Update:https://support.microsoft.com/help/5082413
https://support.microsoft.com/help/5082413
FixedMicrosoft .NET Framework 3.5 AND 4.8msrc_csaf
2.0.50727.9068 & 3.0.30729.9065 & 4.8.4801.0:Security Update:https://support.microsoft.com/help/5082414
https://support.microsoft.com/help/5082414
FixedMicrosoft .NET Framework 3.5 AND 4.8.1msrc_csaf
2.0.50727.9181 & 3.0.30729.9165 & 4.8.9332.0:Security Update:https://support.microsoft.com/help/5082417
https://support.microsoft.com/help/5082417
FixedMicrosoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2msrc_csaf
4.8.4801.0:Security Update:https://support.microsoft.com/help/5082400
https://support.microsoft.com/help/5082400
FixedMicrosoft .NET Framework 4.8msrc_csaf
4.8.4801.0:Security Update:https://support.microsoft.com/help/5082403
https://support.microsoft.com/help/5082403

cvss

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

7.5

010

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

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · secure@microsoft.com USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · NCSC-NL NL

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · Microsoft Security Response Center US

ssvc

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

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-366USCWE-755USCWE-755USCWE-755US

affected products (156)

Products and version ranges known to be affected.

Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Hitachi Virtual Storage Platform 5100all versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5100
Hitachi Virtual Storage Platform 5100Hall versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5100h
Hitachi Virtual Storage Platform 5200all versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5200
Hitachi Virtual Storage Platform 5200Hall versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5200h
Hitachi Virtual Storage Platform 5500all versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5500
Hitachi Virtual Storage Platform 5500Hall versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5500h
Hitachi Virtual Storage Platform 5600all versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5600
Hitachi Virtual Storage Platform 5600Hall versionscert_bundDEcpe:/h:hitachi:virtual_storage_platform:5600h
Microsoft .NET 10.0all versionscert_bundDEcpe:/a:microsoft:.net:10.0
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 4.7.2all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.7.2
Microsoft .NET Framework 4.8all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.8
Microsoft .NET Framework 4.8.1all versionscert_bundDEcpe:/a:microsoft:.net_framework:4.8.1
Microsoft PowerShell 7.4all versionscert_bundDEcpe:/a:microsoft:powershell:7.4:rc1
Microsoft PowerShell 7.5all versionscert_bundDEcpe:/a:microsoft:powershell:7.5
Microsoft Visual Studio 2017 version 15.9 (includes 15.0-15.8)all versionscert_bundDE
Microsoft Visual Studio 2019 version 16.11 (includes 16.0-16.10)all versionscert_bundDE

showing 20 of 156

advisories (4)

Vendor and ecosystem advisories describing this.

NCSC-2026-0114Kwetsbaarheden verholpen in Microsoft Developer toolsNL2026-04-14csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in .NET, .NET Framework, Visual Studio en PowerShell.
WID-SEC-W-2026-1100Microsoft DeveloperTools: Mehrere SchwachstellenDeutsch2026-04-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Microsoft Visual Studio, Microsoft .NET Framework, Microsoft .NET, Microsoft PowerShell und Microsoft Visual Studio Code ausnutzen, um vertrauliche Informationen offenzulegen, Spoofing-Angriffe durchzuführen, einen Denial-of-Service-Zustand herbeizuführen oder Sicherheitsmaßnahmen zu umgehen, was möglicherweise die Ausführung von beliebigem Code ermöglicht.
msrc_CVE-2026-23666.NET Framework Denial of Service Vulnerability2026-04-14csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
JVNDB-2026-018098JVN iPedia advisory JVNDB-2026-0180982026-06-04vendor · jvndbJP

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund ncsc_nl msrc_csaf jvndb NVD CVE.org MITRE

published 2026-04-14modified 2026-07-15

references (7)

External citations — patches, advisories, analysis.

scry

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