Microsoft .NET Framework prior 4.8.9332.0 exceptional condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Microsoft .NET Framework. This affects an unknown part. Such manipulation leads to exceptional condition. This vulnerability is uniquely identified as CVE-2026-23666. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft .NET Framework. Affected by this issue is an unknown function. The manipulation with an unknown input leads to a exceptional condition vulnerability. Using CWE to declare the problem leads to CWE-755. The product does not handle or incorrectly handles an exceptional condition. Impacted is availability. CVE summarizes:

Improper input validation in .NET Framework allows an unauthorized attacker to deny service over a network.

The weakness was disclosed 04/14/2026 as confirmed security update guide (Website). The advisory is shared for download at msrc.microsoft.com. This vulnerability is handled as CVE-2026-23666. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/02/2026).

It is declared as proof-of-concept.

Upgrading to version 2.0.50727.8982, 2.0.50727.9068, 2.0.50727.9068, 2.0.50727.9181, 2.0.50727.9181, 3.0.30729.8976, 3.0.30729.9065, 3.0.30729.9065, 3.0.30729.9165, 3.0.30729.9165, 4.7.4141.0, 4.7.4141.0, 4.8.4801.0, 4.8.4801.0, 4.8.4801.0 or 4.8.9332.0 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1100). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Microsoft .NET Framework
  • Microsoft PowerShell
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • Oracle Linux
  • RESF Rocky Linux
  • Microsoft .NET
  • Microsoft Visual Studio 2017
  • Microsoft Visual Studio Code
  • Microsoft Visual Studio 2022
  • Microsoft Visual Studio 2019

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.5
VulDB Temp Score: 6.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.5
Vendor Vector (Microsoft): 🔒

CNA Base Score: 7.5
CNA Vector (Microsoft): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Exceptional condition
CWE: CWE-755
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Proof-of-Concept

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Upgrade: .NET Framework 2.0.50727.8982/2.0.50727.9068/2.0.50727.9068/2.0.50727.9181/2.0.50727.9181/3.0.30729.8976/3.0.30729.9065/3.0.30729.9065/3.0.30729.9165/3.0.30729.9165/4.7.4141.0/4.7.4141.0/4.8.4801.0/4.8.4801.0/4.8.4801.0/4.8.9332.0

Timelineinfo

04/14/2026 VulDB entry created
04/14/2026 +0 days Advisory disclosed
04/14/2026 +0 days Countermeasure disclosed
07/02/2026 +78 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-23666 (🔒)
GCVE (CVE): GCVE-0-2026-23666
GCVE (VulDB): GCVE-100-357392
CERT Bund: WID-SEC-2026-1100 - Microsoft DeveloperTools: Mehrere Schwachstellen

Entryinfo

Created: 04/14/2026 19:17
Updated: 07/02/2026 05:48
Changes: 04/14/2026 19:17 (38), 04/14/2026 19:23 (34), 04/18/2026 19:50 (7), 04/22/2026 08:11 (1), 07/02/2026 05:48 (11)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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