Highest advisory severityHigh 2 vendors · 2 advisories

CVE-2026-84008: .NET Denial of Service Vulnerability

Not in the CISA KEV catalog. High advisory severity (CVSS 7.5, MS Server).

Compare the source-linked records below. Ratings and product/version details belong to each advisory; they are not a single CVE-wide score or proof that every listed product is affected. How VulniPulse collects and checks evidence.

NVD detail CVE.org

CVE-2026-84008 key facts

CISA KEV: Not listed (catalog checked Nov 6, 2026)
Highest advisory severity: High
CVSS base score: 7.5 (MS Server), 7.5 (Red Hat)
Weakness: CWE-1333
Fixed releases: MS Server: KB5127666 (build 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0), KB5127696 (build 2.0.50727.9188 AND 3.0.30729.9171), KB5127660 (build 2.0.50727.8987 AND 3.0.30729.8982), KB5127664 (build 2.0.50727.8987 AND 3.0.30729.8982), KB5126868 (build 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0), KB5127685 (build 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0) and 2 more in the advisory
Red Hat: dotnet8.0-0:8.0.132-1.el9_4, dotnet9.0-0:9.0.122-1.el10_0, dotnet9.0-0:9.0.122-1.el10_2, dotnet8.0-0:8.0.132-1.el10_2, dotnet8.0-0:8.0.132-2.el8_10, dotnet8-0-main-8.0.132-0.1.hum1 and 8 more in the advisory
Vendor advisories: 2 from MS Server, Red Hat
VulniPulse record: Published Oct 13, 2026 · Updated Oct 31, 2026

Scores, vectors, weaknesses and fixed releases are quoted from vendor advisories that cover only CVE-2026-84008; bulletin-wide values are not repeated here.

Is CVE-2026-84008 exploited?

No exploitation is reported in the sources VulniPulse tracks: CVE-2026-84008 is not in the CISA KEV catalog (checked Nov 6, 2026) and no tracked advisory for it reports exploitation. That is not proof the vulnerability cannot be exploited.

How do I fix CVE-2026-84008?

Upgrade to a fixed release named by the vendor:

MS Server: KB5127666 (build 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0), KB5127696 (build 2.0.50727.9188 AND 3.0.30729.9171), KB5127660 (build 2.0.50727.8987 AND 3.0.30729.8982), KB5127664 (build 2.0.50727.8987 AND 3.0.30729.8982), KB5126868 (build 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0), KB5127685 (build 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0)
Red Hat: dotnet8.0-0:8.0.132-1.el9_4, dotnet9.0-0:9.0.122-1.el10_0, dotnet9.0-0:9.0.122-1.el10_2, dotnet8.0-0:8.0.132-1.el10_2, dotnet8.0-0:8.0.132-2.el8_10, dotnet8-0-main-8.0.132-0.1.hum1

Install the applicable security update for your platform: KB5127666, KB5127696, KB5127660, KB5127664, KB5126868, KB5127685 (see the Microsoft Update Catalog). (MS Server)

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Vendor advisory comparison

MS Server

1 advisory

Advisory severityHigh7.5
High [CVE-2026-84008] .NET Denial of Service Vulnerability
CVE-2026-84008Source published Oct 13, 2026
.NET Denial of Service Vulnerability Affected products named by the advisory: Microsoft.NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2019; Microsoft.NET Framework 3.5 on Windows Server 2012; Microsoft.NET Framework 3.5 on Windows Server 2012 R2; Microsoft.NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2016; and 4 more. Affected products named by the advisory: Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019; Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2022; Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 R2.
Affected products in this advisory
Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2019
Microsoft .NET Framework 3.5 on Windows Server 2012 R2
Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2016
Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019
2 more entries in the full advisory.
Source-reported affected versions
Affected-version details not available in this record.
Source-reported fixed versions
KB5127666 (build 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0)
KB5127696 (build 2.0.50727.9188 AND 3.0.30729.9171)
KB5127660 (build 2.0.50727.8987 AND 3.0.30729.8982)
KB5127664 (build 2.0.50727.8987 AND 3.0.30729.8982)
4 more entries in the full advisory.
Mitigation guidance
Install the applicable security update for your platform: KB5127666, KB5127696, KB5127660, KB5127664, KB5126868, KB5127685 (see the Microsoft Update Catalog).
Full advisory and evidence Open source bulletin

Red Hat

1 advisory

Advisory severityHigh7.5
High [CVE-2026-84008] .NET Denial of Service Vulnerability
CVE-2026-84008Source published Oct 13, 2026Source updated Oct 13, 2026
.NET Denial of Service Vulnerability. Red Hat rates this important (CVSS 7.5). Weakness: CWE-1333. Red Hat lists fixing advisory RHSA-2026:86171 with package dotnet8.0-0:8.0.132-1.el9_4, dotnet9.0-0:9.0.122-1.el10_0, dotnet9.0-0:9.0.122-1.el10_2, dotnet8.0-0:8.0.132-1.el10_2. Affected products named by the advisory: Red Hat Enterprise Linux 9; Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8.
Related products — impact not confirmed
Red Hat Enterprise Linux 9
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 8
Source-reported affected versions
Affected-version details not available in this record.
Source-reported fixed versions
dotnet8.0-0:8.0.132-1.el9_4
dotnet9.0-0:9.0.122-1.el10_0
dotnet9.0-0:9.0.122-1.el10_2
dotnet8.0-0:8.0.132-1.el10_2
10 more entries in the full advisory.
Mitigation guidance
No mitigation guidance extracted; consult the source.
Full advisory and evidence Open source bulletin

All MS Server advisories

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