CVE-2026-97801: CWE-1287: Improper Validation of Specified Type of Input in Microsoft Microsoft .NET Framework 3.5
Description
Improper validation of specified type of input in .NET Framework allows an unauthorized attacker to perform tampering over a network.
CVSS v3.1
Score 7.5high
Affected software
Microsoft
Microsoft .NET Framework 3.5
Microsoft
Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2
Microsoft
Microsoft .NET Framework 3.5 AND 4.7.2
Microsoft
Microsoft .NET Framework 3.5 AND 4.8
Microsoft
Microsoft .NET Framework 3.5 AND 4.8.1
Microsoft
Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2
Microsoft
Microsoft .NET Framework 4.8
Microsoft
Microsoft .NET Framework 4.8.1
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-97801 is a vulnerability classified under CWE-1287 (Improper Validation of Specified Type of Input) affecting Microsoft .NET Framework 3.5 and related versions. The vulnerability allows an attacker to tamper with data over a network due to insufficient validation of input types. It has a CVSS 3.1 base score of 7.5, indicating high severity, with network attack vector, low attack complexity, no privileges required, and no user interaction needed. Microsoft has published an official fix for this vulnerability.
Potential Impact
An unauthorized attacker can perform tampering over a network without requiring privileges or user interaction. The vulnerability does not impact confidentiality or availability but impacts integrity. This could allow modification or manipulation of data or processes within affected .NET Framework applications.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security updates provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97801 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-25T04:41:33.499Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97801","vendor":"Microsoft"}]
Threat ID: 6ace85952cdf04f656a018f3
Added to database: 10/13/2026, 19:25:09 UTC
Last enriched: 10/13/2026, 22:48:56 UTC
Last updated: 10/14/2026, 03:08:28 UTC
Views: 4
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