CVE-2026-23666: CWE-755: Improper Handling of Exceptional Conditions in Microsoft Microsoft .NET Framework 3.5
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
AI Analysis
Technical Summary
This vulnerability in Microsoft .NET Framework 3.5 arises from improper input validation, which leads to improper handling of exceptional conditions (CWE-755). Exploitation allows an unauthenticated attacker to remotely cause a denial of service (DoS) condition, impacting availability. The CVSS v3.1 base score is 7.5, reflecting network attack vector, low attack complexity, no privileges or user interaction required, and a high impact on availability only. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker can remotely cause a denial of service in affected versions of Microsoft .NET Framework 3.5 by exploiting improper input validation. This impacts the availability of services relying on the framework. There is no impact on confidentiality or integrity. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23666 to remediate this vulnerability.
CVE-2026-23666: CWE-755: Improper Handling of Exceptional Conditions in Microsoft Microsoft .NET Framework 3.5
Description
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Microsoft .NET Framework 3.5 arises from improper input validation, which leads to improper handling of exceptional conditions (CWE-755). Exploitation allows an unauthenticated attacker to remotely cause a denial of service (DoS) condition, impacting availability. The CVSS v3.1 base score is 7.5, reflecting network attack vector, low attack complexity, no privileges or user interaction required, and a high impact on availability only. Microsoft has published an official fix for this vulnerability.
Potential Impact
An attacker can remotely cause a denial of service in affected versions of Microsoft .NET Framework 3.5 by exploiting improper input validation. This impacts the availability of services relying on the framework. There is no impact on confidentiality or integrity. No known exploits are reported in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23666 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-01-14T16:59:33.464Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23666","vendor":"Microsoft"}]
Threat ID: 69de7a1482d89c981fd6a5f2
Added to database: 4/14/2026, 5:32:04 PM
Last enriched: 5/19/2026, 10:32:22 AM
Last updated: 5/31/2026, 2:41:28 AM
Views: 68
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