Description
Improper certificate validation in Active Directory Federation Services (AD FS) allows an unauthorized attacker to perform spoofing over a network.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Microsoft | Microsoft .NET Framework 3.5 | 3.5.0 – < 2.0.50727.9188 AND 3.0.30729.9171 | 2.0.50727.9188 AND 3.0.30729.9171 |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 | 3.0.0.0 – < 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 | 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.7.2 | 4.7.0 – < 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.8 | 4.8.0 – < 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.8.1 | 4.8.1 – < 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 | 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 |
| Microsoft | Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 | 4.7.0 – < 4.7.4150.0 | 4.7.4150.0 |
| Microsoft | Microsoft .NET Framework 4.8 | 4.8.0 – < 4.8.4811.0 | 4.8.4811.0 |
| Microsoft | Microsoft .NET Framework 4.8.1 | 4.8.0.0 – < 4.8.9363.0 | 4.8.9363.0 |
| Microsoft | Microsoft Visual Studio 2022 version 17.14 | 17.14.0 – < 17.14.42 | 17.14.42 |
| Microsoft | Microsoft Visual Studio 2026 version 18.10 | 18.10.0 – < 18.10.4 | 18.10.4 |
| Microsoft | System.Security.Cryptography.Xml | 10.0.0 – < 8.0.5 | 8.0.5 |
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 – < 10.0.14393.9612 | 10.0.14393.9612 |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 – < 10.0.17763.9376 | 10.0.17763.9376 |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 – < 6.3.9600.23470 | 6.3.9600.23470 |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 – < 6.3.9600.23470 | 6.3.9600.23470 |
| Microsoft | Windows Server 2016 | 10.0.14393.0 – < 10.0.14393.9612 | 10.0.14393.9612 |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 – < 10.0.14393.9612 | 10.0.14393.9612 |
| Microsoft | Windows Server 2019 | 10.0.17763.0 – < 10.0.17763.9376 | 10.0.17763.9376 |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 – < 10.0.17763.9376 | 10.0.17763.9376 |
| Microsoft | Windows Server 2022 | 10.0.20348.0 – < 10.0.20348.5761 | 10.0.20348.5761 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – < 10.0.26100.33650 | 10.0.26100.33650 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – < 10.0.26100.33650 | 10.0.26100.33650 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | dotnet10 | 10.0.113-10.0.13-0ubuntu1~26.10.1 | USN-8942-1 |
| Ubuntu 26.10 | dotnet11 | 11.0.100-11.0.0~rc2-0ubuntu1~26.10.1 | USN-8942-1 |
| Ubuntu 26.04 LTS | dotnet10 | 10.0.113-10.0.13-0ubuntu1~26.04.1 | USN-8942-1 |
| Ubuntu 24.04 LTS | dotnet10 | 10.0.113-10.0.13-0ubuntu1~24.04.1 | USN-8942-1 |
| Ubuntu 24.04 LTS | dotnet8 | 8.0.132-8.0.32-0ubuntu1~24.04.1 | USN-8942-1 |
| Ubuntu 22.04 LTS | dotnet6 +1 | No fix yet | — |
| Ubuntu 22.04 LTS | dotnet8 | 8.0.132-8.0.32-0ubuntu1~22.04.1 | USN-8942-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el10_2 | RHSA-2026:86168 |
| RHEL 10 | dotnet8.0 +4 | 8.0.132-1.el10_2 | RHSA-2026:86168 |
| RHEL 9 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el9_8 | RHSA-2026:86169 |
| RHEL 9 | dotnet8.0 +4 | 8.0.132-1.el9_8 | RHSA-2026:86169 |
| RHEL 8 | dotnet-hostfxr-8.0 +7 | 8.0.32-2.el8_10 | RHSA-2026:86594 |
| RHEL 8 | dotnet8.0 +4 | 8.0.132-2.el8_10 | RHSA-2026:86594 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 10.0 EUS | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el10_0 | RHSA-2026:88474 |
| RHEL 10.0 EUS | dotnet8.0 +4 | 8.0.132-1.el10_0 | RHSA-2026:88474 |
| RHEL 9.6 EUS | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el9_6 | RHSA-2026:88422 |
| RHEL 9.6 EUS | dotnet8.0 +4 | 8.0.132-1.el9_6 | RHSA-2026:88422 |
| RHEL 9.4 E4S | dotnet-host +8 | 8.0.32-1.el9_4 | RHSA-2026:88425 |
| RHEL 9.4 E4S | dotnet8.0 +4 | 8.0.132-1.el9_4 | RHSA-2026:88425 |
| Red Hat Hardened Images 1 | dotnet-hostfxr-8.0 +7 | 8.0.32-0.1.hum1 | RHSA-2026:84693 |
| Red Hat Hardened Images 1 | dotnet8.0 +4 | 8.0.132-0.1.hum1 | RHSA-2026:84693 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 10 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el10_2 | ALSA-2026:86168 |
| AlmaLinux 10 | dotnet-sdk-8.0 +3 | 8.0.132-1.el10_2 | ALSA-2026:86168 |
| AlmaLinux 9 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.el9_8 | ALSA-2026:86169 |
| AlmaLinux 9 | dotnet-sdk-8.0 +3 | 8.0.132-1.el9_8 | ALSA-2026:86169 |
| AlmaLinux 8 | dotnet-hostfxr-8.0 +7 | 8.0.32-2.el8_10 | ALSA-2026:86594 |
| AlmaLinux 8 | dotnet-sdk-8.0 +3 | 8.0.132-2.el8_10 | ALSA-2026:86594 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 10 | dotnet8.0 | 8.0.132-1.el10_2 | RLSA-2026:86168 |
| Rocky Linux 9 | dotnet8.0 | 8.0.132-1.el9_8 | RLSA-2026:86169 |
| Rocky Linux 8 | dotnet8.0 | 8.0.132-2.el8_10 | RLSA-2026:86594 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | dotnet8-runtime | 8.0.32-r0 | — |
| Alpine v3.23 | dotnet8-runtime | 8.0.32-r0 | — |
| Alpine v3.22 | dotnet8-runtime | 8.0.32-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | dotnet +5 | 8.0.133-1.amzn2023.0.1 | ALAS2023-2026-3367 |
| Amazon Linux 2023 | dotnet-host +8 | 8.0.33-1.amzn2023.0.1 | ALAS2023-2026-3367 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 10 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.0.1.el10_2 | ELSA-2026-86168 |
| Oracle Linux 10 | dotnet-sdk-8.0 +3 | 8.0.132-1.0.1.el10_2 | ELSA-2026-86168 |
| Oracle Linux 9 | dotnet-hostfxr-8.0 +7 | 8.0.32-1.0.1.el9_8 | ELSA-2026-86169 |
| Oracle Linux 9 | dotnet-sdk-8.0 +3 | 8.0.132-1.0.1.el9_8 | ELSA-2026-86169 |
| Oracle Linux 8 | dotnet-hostfxr-8.0 +7 | 8.0.32-2.0.1.el8_10 | ELSA-2026-86594 |
| Oracle Linux 8 | dotnet-sdk-8.0 +3 | 8.0.132-2.0.1.el8_10 | ELSA-2026-86594 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | dotnet-8-sdk | 8.0.132-r0 | — |
| Wolfi rolling | dotnet-bootstrap-8 | 8.0.134-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| NuGet | System.Security.Cryptography.Xml | >= 8.0.0, < 8.0.5 | 8.0.5 | GHSA-vrv5-2jg9-4mmr |
Advisories 21
- RHSA-2026:84693 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:88474 Red Hat Security Advisory: .NET 8.0 security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:88425 Red Hat Security Advisory: .NET 8.0 security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:88422 Red Hat Security Advisory: .NET 8.0 security update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:86594 Red Hat Security Advisory: .NET 8.0 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:86169 Red Hat Security Advisory: .NET 8.0 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:86168 Red Hat Security Advisory: .NET 8.0 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2026-3892 Microsoft Windows und Windows Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
- WID-SEC-2026-3893 Microsoft Entwicklerwerkzeuge: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 4, 2026
- ALSA-2026:86594 Critical: .NET 8.0 security, bug fix, and enhancement update AlmaLinux Security Advisories · Nov 2, 2026
- ALAS2023-2026-3367 Important: dotnet8.0 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 2, 2026
- ALSA-2026:86168 Critical: .NET 8.0 security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 31, 2026
- ALSA-2026:86169 Critical: .NET 8.0 security, bug fix, and enhancement update AlmaLinux Security Advisories · Oct 31, 2026
- USN-8942-1 dotnet8, dotnet10, dotnet11 vulnerabilities Ubuntu Security Notices (USN) · Oct 30, 2026
- RLSA-2026:86168 Critical: .NET 8.0 security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 22, 2026
- RLSA-2026:86169 Critical: .NET 8.0 security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 22, 2026
- RLSA-2026:86594 Critical: .NET 8.0 security, bug fix, and enhancement update Rocky Linux Security Advisories · Oct 22, 2026
- ELSA-2026-86168 Critical: .NET 8.0 security, bug fix, and enhancement update (Oracle Linux 10) Oracle Linux Security Advisories (ELSA) · Oct 21, 2026
- ELSA-2026-86169 Critical: .NET 8.0 security, bug fix, and enhancement update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 21, 2026
- ELSA-2026-86594 Critical: .NET 8.0 security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Oct 21, 2026
- MSRC-CVE-2026-96222 Active Directory Federation Services (AD FS) Spoofing Vulnerability Microsoft Security Response Center · Oct 16, 2026
References
- Active Directory Federation Services (AD FS) Spoofing Vulnerability vendor-advisory patch