CVE-2026-23666: CWE-755: Improper Handling of Exceptional Conditions in Microsoft Microsoft .NET Framework 3.5
CVE-2026-23666 is a high-severity vulnerability in Microsoft . NET Framework 3. 5 involving improper synchronization during concurrent execution of shared resources, leading to a race condition. This flaw allows an unauthorized attacker to cause a denial of service (DoS) over a network. An official fix has been released by Microsoft to address this issue.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-23666) affects Microsoft .NET Framework 3.5 (version 3.5.0) and is classified under CWE-755 for improper handling of exceptional conditions. It arises from a race condition due to improper synchronization when multiple threads concurrently access shared resources. Exploitation can result in denial of service by disrupting normal application operation. The vulnerability has a CVSS v3.1 base score of 7.5, indicating high severity. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation of this vulnerability allows an unauthorized attacker to cause a denial of service condition over the network, impacting availability of applications relying on the affected .NET Framework version. There is no impact on confidentiality or integrity according to the CVSS vector. 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. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-23666: CWE-755: Improper Handling of Exceptional Conditions in Microsoft Microsoft .NET Framework 3.5
Description
CVE-2026-23666 is a high-severity vulnerability in Microsoft . NET Framework 3. 5 involving improper synchronization during concurrent execution of shared resources, leading to a race condition. This flaw allows an unauthorized attacker to cause a denial of service (DoS) over a network. An official fix has been released by Microsoft to address this issue.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-23666) affects Microsoft .NET Framework 3.5 (version 3.5.0) and is classified under CWE-755 for improper handling of exceptional conditions. It arises from a race condition due to improper synchronization when multiple threads concurrently access shared resources. Exploitation can result in denial of service by disrupting normal application operation. The vulnerability has a CVSS v3.1 base score of 7.5, indicating high severity. Microsoft has published an official fix to remediate this issue.
Potential Impact
Successful exploitation of this vulnerability allows an unauthorized attacker to cause a denial of service condition over the network, impacting availability of applications relying on the affected .NET Framework version. There is no impact on confidentiality or integrity according to the CVSS vector. 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. No additional mitigation steps are indicated by the vendor advisory.
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: 4/14/2026, 7:18:46 PM
Last updated: 4/15/2026, 6:08:47 AM
Views: 3
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