CVE-2026-23666
.NET Framework Denial of Service Vulnerability
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
.NET Framework Denial of Service Vulnerability
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
- Record
CVE-2026-23666- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755, CWE-366
- Updated
- 2026-11-02
EUVDEUVD-2026-22363
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
- Record
EUVD-2026-22363- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fvc9-q887-5p2h
Concurrent execution using shared resource with improper synchronization ('race condition') in ...
Concurrent execution using shared resource with improper synchronization ('race condition') in .NET Framework allows an unauthorized attacker to deny service over a network.
- Record
GHSA-fvc9-q887-5p2h- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-366, CWE-755
- Updated
- 2026-11-02
NVD
Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.
- Record
CVE-2026-23666- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755, CWE-366
- Updated
- 2026-11-02
Affected products
- microsoft .net framework
- microsoft .net framework 3.5
- microsoft .net framework 3.5 and 4.7.2
- microsoft .net framework 3.5 and 4.8
- microsoft .net framework 3.5 and 4.8.1
- microsoft .net framework 4.6.2/4.7/4.7.1/4.7.2
- microsoft .net framework 4.8
- red hat enterprise linux 10
- red hat enterprise linux 8
- red hat enterprise linux 9
- red hat hardened images
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-23666 is a high vulnerability (CVSS 7.5) in Microsoft .net Framework, published April 14, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.33%, the 71st percentile. No source names a fixed version.