CVE-2026-32203: .NET and Visual Studio Denial of Service Vulnerability
CVE-2026-32203 is a denial of service vulnerability in .NET and Visual Studio, rated Important by Microsoft, with a CVSS 3.1 base score of 7.5 (High). An attacker can exploit it remotely over the network, without any privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 1.90% probability of exploitation activity in the next 30 days, higher than 80% of all scored vulnerabilities. Microsoft released the fix on 14 April 2026 in the April 2026 Patch Tuesday, delivered through 3 security updates (KB5086095, KB5086096, KB5086097). It affects 12 products in 1 product family (Developer Tools).
Key facts
- CVE ID
- CVE-2026-32203
- Severity
- High CVSS 7.5
- Microsoft severity
- Important
- Impact
- Denial of Service
- Exploited in the wild
- No
- Publicly disclosed
- No
- Exploitation likelihood
- Less Likely
- Weakness
- CWE-20; CWE-121
- EPSS
- 1.90% (percentile 80%)
- CISA KEV
- Not listed
- Released
- Last updated
- Patch Tuesday
- April 2026 Patch Tuesday
- Product families
- Developer Tools
CVSS score and vector
Microsoft scores CVE-2026-32203 at 7.5 (temporal 6.5) using CVSS 3.1. Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
| Metric | Value |
|---|---|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality impact | None |
| Integrity impact | None |
| Availability impact | High |
| Exploit code maturity | Unproven |
| Remediation level | Official fix |
| Report confidence | Confirmed |
Description
Stack-based buffer overflow in .NET and Visual Studio allows an unauthorized attacker to deny service over a network.
Affected products (12)
Developer Tools
| Product | Security update | Type | Fixed build | Restart |
|---|---|---|---|---|
| Microsoft Visual Studio 2026 version 18.4 | Release Notes | Security Update | 18.4.4 | Maybe |
| Microsoft Visual Studio 2022 version 17.12 | Release Notes | Security Update | 17.12.19 | Maybe |
| Microsoft Visual Studio 2022 version 17.14 | Release Notes | Security Update | 17.14.30 | Maybe |
| .NET 10.0 installed on Windows | KB5086095 | Security Update | 10.0.6 | Maybe |
| .NET 10.0 installed on Mac OS | KB5086095 | Security Update | 10.0.6 | Maybe |
| .NET 10.0 installed on Linux | KB5086095 | Security Update | 10.0.6 | Maybe |
| .NET 8.0 installed on Windows | KB5086096 | Security Update | 8.0.26 | Maybe |
| .NET 8.0 installed on Linux | KB5086096 | Security Update | 8.0.26 | Maybe |
| .NET 8.0 installed on Mac OS | KB5086096 | Security Update | 8.0.26 | Maybe |
| .NET 9.0 installed on Linux | KB5086097 | Security Update | 9.0.15 | Maybe |
| .NET 9.0 installed on Mac OS | KB5086097 | Security Update | 9.0.15 | Maybe |
| .NET 9.0 installed on Windows | KB5086097 | Security Update | 9.0.15 | Maybe |
Security updates (3)
NIST NVD data
Affected configurations (CPE)
| Product | Vulnerable versions |
|---|---|
| .net | from 10.0.0, before 10.0.6 |
| .net | from 8.0.0, before 8.0.26 |
| .net | from 9.0.0, before 9.0.15 |
| visual studio 2022 | from 17.12.0, before 17.12.19 |
| visual studio 2022 | from 17.14.0, before 17.14.30 |
| visual studio 2026 | from 18.4.0, before 18.4.4 |
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-32203 (Vendor Advisory)
Acknowledgments
- Ludvig Pedersen
- vcsjones with GitHub
Revision history
| Version | Date | Description |
|---|---|---|
| 1.0 | Information published. | |
| 1.1 | Download links fixed |