MSRC_CVE-2026-42899

Vulnerability from csaf_microsoft - Published: 2026-05-12 07:00 - Updated: 2026-05-12 07:00
Summary
ASP.NET Core Denial of Service Vulnerability
Severity
Important
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Customer Action: Required. The vulnerability documented by this CVE requires customer action to resolve.
CVE-2026-42899
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Affected products
Product Identifier Version Remediation
.NET 8.0 installed on Windows 8.0.27
.NET 8.0 installed on Windows
 8.0.27
.NET 8.0 installed on Linux 8.0.27
.NET 8.0 installed on Linux
 8.0.27
.NET 8.0 installed on Mac OS 8.0.27
.NET 8.0 installed on Mac OS
 8.0.27
.NET 9.0 installed on Linux 9.0.16
.NET 9.0 installed on Linux
 9.0.16
.NET 9.0 installed on Mac OS 9.0.16
.NET 9.0 installed on Mac OS
 9.0.16
.NET 9.0 installed on Windows 9.0.16
.NET 9.0 installed on Windows
 9.0.16
.NET 10.0 installed on Windows 10.0.8
.NET 10.0 installed on Windows
 10.0.8
.NET 10.0 installed on Mac OS 10.0.8
.NET 10.0 installed on Mac OS
 10.0.8
.NET 10.0 installed on Linux 10.0.8
.NET 10.0 installed on Linux
 10.0.8
Product Identifier Version Remediation
.NET 10.0 installed on Linux <10.0.8
.NET 10.0 installed on Linux
 <10.0.8
Vendor Fix fix
.NET 10.0 installed on Mac OS <10.0.8
.NET 10.0 installed on Mac OS
 <10.0.8
Vendor Fix fix
.NET 10.0 installed on Windows <10.0.8
.NET 10.0 installed on Windows
 <10.0.8
Vendor Fix fix
.NET 9.0 installed on Windows <9.0.16
.NET 9.0 installed on Windows
 <9.0.16
Vendor Fix fix
.NET 9.0 installed on Mac OS <9.0.16
.NET 9.0 installed on Mac OS
 <9.0.16
Vendor Fix fix
.NET 9.0 installed on Linux <9.0.16
.NET 9.0 installed on Linux
 <9.0.16
Vendor Fix fix
.NET 8.0 installed on Mac OS <8.0.27
.NET 8.0 installed on Mac OS
 <8.0.27
Vendor Fix fix
.NET 8.0 installed on Linux <8.0.27
.NET 8.0 installed on Linux
 <8.0.27
Vendor Fix fix
.NET 8.0 installed on Windows <8.0.27
.NET 8.0 installed on Windows
 <8.0.27
Vendor Fix fix
Threats
Impact Denial of Service
Exploit Status Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Unlikely
References
Acknowledgments
hamayanhamayan
<a href="https://www.linkedin.com/in/abdul-rehman---/">Muhammad Abdul Rehman</a>
To clipboard 

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        "names": [
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        "title": "Additional Resources"
      },
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        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
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    ],
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      },
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            "confidentialityImpact": "NONE",
            "environmentalsScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 6.5,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
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        {
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          "details": "Denial of Service"
        },
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          "category": "exploit_status",
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        }
      ],
      "title": "ASP.NET Core Denial of Service Vulnerability"
    }
  ]
}


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Tags
Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.