.NET Remote Code Execution Vulnerability

CVE

CVE-2026-87697

Severity

Important

CVSS base score

8.8

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Impact

Remote Code Execution

Exploitation detected

Not reported by MSRC

Publicly disclosed

No

Exploitability

Exploitation Less Likely

Component

.NET

Weakness

CWE-502: Deserialization of Untrusted Data

Issued by

Microsoft

Customer action

Required: apply the update

Affected products

.NET 10.0 runtime installed on Windows, .NET 11.0 runtime installed on Windows, .NET 8.0 runtime installed on Windows, .NET 9.0 runtime installed on Windows, Microsoft Visual Studio 2022 version 17.14, Microsoft Visual Studio 2026 version 18.10

Updates that fix it

KB5130034: .NET 8.0 runtime installed on Windows (restart required); KB5130035: .NET 9.0 runtime installed on Windows (restart required); KB5130036: .NET 10.0 runtime installed on Windows (restart required)

CISA KEV

Not listed in the collected catalog

EPSS

0.8%; scored 24 Oct 2026

Public exploit code

No Nuclei template listed

Published

13 Oct 2026 07:00 UTC

Last revised

15 Oct 2026 07:00 UTC

Revision note

Updated the Security Updates table to add KB article links for .NET 11.0 and download and KB article links for Microsoft Visual Studio. This is an informational change only; the fixed builds are unchanged.

• MSRC advisory
• NVD
• CVE.org
• October 2026
• KB5130034
• KB5130035
• KB5130036

Microsoft security releases

Complete at observationRead 25 Oct 2026 at 01:33 UTC

CISA KEV

Complete at observationRead 25 Oct 2026 at 01:33 UTC

FIRST EPSS

Complete at observationRead 25 Oct 2026 at 01:33 UTC

Public exploit code

Complete at observationRead 25 Oct 2026 at 01:33 UTC

Coverage describes the sources at this observation. A complete read then does not establish their current position.

1. 25 Oct 2026 · 01:34:18 UTC EPSS0.8%; scored 23 Oct 2026 → 0.8%; scored 24 Oct 2026
2. 23 Oct 2026 · 15:51:28 UTC EPSS0.8%; scored 22 Oct 2026 → 0.8%; scored 23 Oct 2026
3. 23 Oct 2026 · 09:33:49 UTC Public exploit codeUnknown: exploit-code evidence is incomplete or retained → No Nuclei template listed
4. 23 Oct 2026 · 09:33:49 UTC CISA KEVUnknown: catalog evidence is incomplete or retained → Not listed in the collected catalog
5. 23 Oct 2026 · 09:33:49 UTC Source coverage: public-exploit-codeIncomplete → Current
6. 23 Oct 2026 · 09:33:49 UTC Source coverage: first-epssIncomplete → Current
7. 23 Oct 2026 · 09:33:49 UTC Source coverage: cisa-kevIncomplete → Current
8. 23 Oct 2026 · 09:33:49 UTC Source coverage: msrc-cvrfIncomplete → Current
9. 23 Oct 2026 · 08:31:50 UTC Public exploit codeNo Nuclei template listed → Unknown: exploit-code evidence is incomplete or retained
10. 23 Oct 2026 · 08:31:50 UTC CISA KEVNot listed in the collected catalog → Unknown: catalog evidence is incomplete or retained
11. 23 Oct 2026 · 08:31:50 UTC Source coverage: public-exploit-codeCurrent → Incomplete
12. 23 Oct 2026 · 08:31:50 UTC Source coverage: first-epssCurrent → Incomplete

The most recent 100 field changes are listed. Complete recorded revisions are kept separately.

Cite this recorded revision to keep the same title, summary, facts and links when the page changes.

A day selects the latest observation by the end of that UTC day; today's selection can change until midnight. History starts when this installation records it.