High

.NET Denial of Service Vulnerability

Type: advisorySource: Official CVE List1 source record

Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.

Announced 13 Oct 2026Source revision 1

CVE-2026-84008

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-84008

Microsoft .NET Framework 3.5

Source reference: /containers/cna/affected/0/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2

Source reference: /containers/cna/affected/1/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 3.5 AND 4.7.2

Source reference: /containers/cna/affected/2/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 3.5 AND 4.8

Source reference: /containers/cna/affected/3/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 3.5 AND 4.8.1

Source reference: /containers/cna/affected/4/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2

Source reference: /containers/cna/affected/5/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 4.8

Source reference: /containers/cna/affected/6/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft .NET Framework 4.8.1

Source reference: /containers/cna/affected/7/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft Visual Studio 2022 version 17.14

Source reference: /containers/cna/affected/8/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Microsoft Visual Studio 2026 version 18.10

Source reference: /containers/cna/affected/9/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

System.Security.Cryptography.Pkcs

Source reference: /containers/cna/affected/10/product

Affected versions: Not stated in this record
Fixed versions: Not stated in this record
Prerequisites: Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 3.5",
    "versions": [
      {
        "status": "affected",
        "version": "3.5.0",
        "lessThan": "2.0.50727.9188 AND 3.0.30729.9171",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 11 version 26H1",
      "Windows Server 2012",
      "Windows Server 2012 R2"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2",
    "versions": [
      {
        "status": "affected",
        "version": "3.0.0.0",
        "lessThan": "2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 10 version 1607",
      "Windows Server 2016",
      "Windows Server 2019"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 3.5 AND 4.7.2",
    "versions": [
      {
        "status": "affected",
        "version": "4.7.0",
        "lessThan": "2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 10 version 1809"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 3.5 AND 4.8",
    "versions": [
      {
        "status": "affected",
        "version": "4.8.0",
        "lessThan": "2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 10 version 1809",
      "Windows 10 version 21H2",
      "Windows 10 version 22H2",
      "Windows Server 2019",
      "Windows Server 2022"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 3.5 AND 4.8.1",
    "versions": [
      {
        "status": "affected",
        "version": "4.8.1",
        "lessThan": "2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 10 version 21H2",
      "Windows 10 version 22H2",
      "Windows 11 version 23H2",
      "Windows 11 version 24H2",
      "Windows 11 version 25H2",
      "Windows 11 version 26H2",
      "Windows Server 2022",
      "Windows Server 2025"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2",
    "versions": [
      {
        "status": "affected",
        "version": "4.7.0",
        "lessThan": "4.7.4150.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows Server 2012",
      "Windows Server 2012 R2"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 4.8",
    "versions": [
      {
        "status": "affected",
        "version": "4.8.0",
        "lessThan": "4.8.4811.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 10 version 1607",
      "Windows Server 2012",
      "Windows Server 2012 R2",
      "Windows Server 2016"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft .NET Framework 4.8.1",
    "versions": [
      {
        "status": "affected",
        "version": "4.8.0.0",
        "lessThan": "4.8.9363.0",
        "versionType": "custom"
      }
    ],
    "platforms": [
      "Windows 11 version 26H1"
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft Visual Studio 2022 version 17.14",
    "versions": [
      {
        "status": "affected",
        "version": "17.14.0",
        "lessThan": "17.14.42",
        "versionType": "custom"
      }
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "Microsoft Visual Studio 2026 version 18.10",
    "versions": [
      {
        "status": "affected",
        "version": "18.10.0",
        "lessThan": "18.10.4",
        "versionType": "custom"
      }
    ]
  },
  {
    "vendor": "Microsoft",
    "product": "System.Security.Cryptography.Pkcs",
    "versions": [
      {
        "status": "affected",
        "version": "10.0.0",
        "lessThan": "10.0.13",
        "versionType": "custom"
      }
    ],
    "platforms": [
      ".NET 10.0 runtime installed on Linux",
      ".NET 10.0 runtime installed on Mac OS",
      ".NET 10.0 runtime installed on Windows",
      ".NET 11.0 runtime installed on Linux",
      ".NET 11.0 runtime installed on Mac OS",
      ".NET 11.0 runtime installed on Windows",
      ".NET 8.0 runtime installed on Linux",
      ".NET 8.0 runtime installed on Mac OS",
      ".NET 8.0 runtime installed on Windows",
      ".NET 9.0 runtime installed on Linux",
      ".NET 9.0 runtime installed on Mac OS",
      ".NET 9.0 runtime installed on Windows"
    ]
  }
]

Related CVEs: CVE-2026-84008
Source reference: /cveMetadata/cveId

Publisher severity

high

Source reference: /containers/cna/metrics

Event: #55090 · Revision 1
Added to Heist Feed: Sun, 25 Oct 2026 15:29:52 GMT
Publisher date: Tue, 13 Oct 2026 19:01:15 GMT

Read the original announcement