CVE-2026-87697
published 2026-10-13CVE-2026-87697: Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code over a network.
PriorityP258high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.84%
57.7th percentile
Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code over a network.
Affected
6 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_visual_studio_2022_version_17.14 | >= 17.14.0 < 17.14.42 | 17.14.42 |
| microsoft | microsoft_visual_studio_2026_version_18.10 | >= 18.10.0 < 18.10.4 | 18.10.4 |
| microsoft | net_10.0_runtime | >= 10.0.0 < 10.0.13 | 10.0.13 |
| microsoft | net_11.0_runtime | >= 11.0.0 < 11.0.0-rc.2 | 11.0.0-rc.2 |
| microsoft | net_8.0_runtime | >= 8.0.0 < 8.0.32 | 8.0.32 |
| microsoft | net_9.0_runtime | >= 9.0.0 < 9.0.21 | 9.0.21 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
ghsa8.8HIGH
vendor_redhat8.8HIGH
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Red Hat
dotnet: dotnet: arbitrary code execution via untrusted data deserialization
vendor_redhat·2026-10-13·CVSS 8.8
CVE-2026-87697 [HIGH] CWE-502 dotnet: dotnet: arbitrary code execution via untrusted data deserialization
dotnet: dotnet: arbitrary code execution via untrusted data deserialization
A flaw was found in dotnet. A remote attacker can achieve arbitrary code execution by tricking an application or user into processing maliciously crafted data during deserialization (the process of reconstructing data into an application object). Successful exploitation allows the attacker to execute unauthorized code over the network within the context of the running application.
Package: dotnet8.0 (Red Hat Hardened Images) - Affected
VulDB
Microsoft .NET/Visual Studio WPF XPS Synthetic Hyperlinks deserialization
vuldb·2026-10-14·CVSS 8.8
CVE-2026-87697 [HIGH] Microsoft .NET/Visual Studio WPF XPS Synthetic Hyperlinks deserialization
A vulnerability categorized as problematic has been discovered in Microsoft .NET and Visual Studio. Affected by this issue is some unknown functionality of the component WPF XPS Synthetic Hyperlinks. Such manipulation leads to deserialization.
This vulnerability is listed as CVE-2026-87697. The attack may be performed from remote. There is no available exploit.
It is best practice to apply a patch to resolve this issue.
GHSA
Microsoft Security Advisory CVE-2026-87697 - .NET and Visual Studio Remote Code Execution Vulnerability
ghsa·2026-10-13·CVSS 8.8
CVE-2026-87697 [HIGH] CWE-502 Microsoft Security Advisory CVE-2026-87697 - .NET and Visual Studio Remote Code Execution Vulnerability
Microsoft Security Advisory CVE-2026-87697 - .NET and Visual Studio Remote Code Execution Vulnerability
## Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.WindowsDesktop.App.Runtime (WPF). This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
WPF XPS synthetic hyperlinks exposed through UI Automation can bypass restrictive navigation checks and reach attacker-controlled content, enabling remote code execution after user interaction.
## Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/471
## CVSS Details
- **Version:** 3.1
- **Severity:** High
- **Score:** 8.8
- **Vector:** `CVSS:3.1/AV:N/A
No detection rules found.
No public exploits indexed.
Sans Isc
October 2026 Microsoft Patch Tuesday, (Tue, Oct 13th)
blogs_sans_isc·2026-10-13·CVSS 8.8
CVE-2026-96951 [HIGH] October 2026 Microsoft Patch Tuesday, (Tue, Oct 13th)
October 2026 Microsoft Patch Tuesday
Published: 2026-10-13. Last Updated: 2026-10-13 19:25:52 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
Microsoft today released patches for 1,417 vulnerabilities. 76 of these vulnerabilities are rated critical, with 7 critical vulnerabiilties requiring no customer actions. One vulnerability was disclosed before today's patch Tuesday, and one is already exploited.
CVE-2026-96951: An already exploited Windows Shell Security Feature Bypass Vulnerability. This vulnerabliity allows bypassing the "Mark of the Web" making it easier to exeucte code by sending a malicious message to a user via e-mail or instant messaging. The victim will still have to open the file.
CVE-2026-108398: This vulnerability, a .NET framework security feature bypass, could be
Rapid7
Patch Tuesday - October 2026
blogs_rapid7·2026-10-13·CVSS 8.8
CVE-2026-96951 [HIGH] Patch Tuesday - October 2026
Microsoft is publishing 1,413 own-product vulnerabilities on October 2026 Patch Tuesday , including 1,102 vulnerabilities in Windows. Anyone who enjoyed last month’s record-setting Patch Tuesday will love the October 2026 edition, because it’s much bigger still. As Rapid7 has noted over the course of 2026, there is every reason to suppose that vulnerability volumes will continue to rise. Microsoft is aware of exploitation in the wild for just one of the vulnerabilities published today, as well as public disclosure for two others.
## Windows Shell: zero-day security feature bypass
The Windows Shell is Microsoft’s term for the GUI interaction logic for the entire OS provided by explorer.exe and associated libraries and APIs, and for the second time this year , the Windows Shell is the site
Bugzilla
CVE-2026-96959 dotnet10.0: .NET: Denial of Service via unthrottled resource allocation [fedora-43]
bugzilla·2026-10-23·CVSS 8.8
CVE-2026-96959 [HIGH] CVE-2026-96959 dotnet10.0: .NET: Denial of Service via unthrottled resource allocation [fedora-43]
CVE-2026-96959 dotnet10.0: .NET: Denial of Service via unthrottled resource allocation [fedora-43]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Allocation of resources without limits or throttling in .NET allows an unauthorized attacker to deny service over a network.
Discussion:
Closing/resolving as this was fixed in https://bodhi.fedoraproject.org/updates/FEDORA-2026-c7c459ff4d
Update to .NET SDK 10.0.113 and Runtime 10.0.13
Fixes: CVE-2026-102870,CVE-2026-105016,CVE-2026-58280,CVE-2026-66822,CVE-2026-69651,CVE-2026-70007,CVE-2026-70035,CVE-2026-70159,CVE-2026-70161,CVE-2026-70162,CVE-2026-70165,CVE-2026-7
Bugzilla
CVE-2026-87697 dotnet: dotnet: arbitrary code execution via untrusted data deserialization
bugzilla·2026-10-13·CVSS 8.8
CVE-2026-87697 [HIGH] CVE-2026-87697 dotnet: dotnet: arbitrary code execution via untrusted data deserialization
CVE-2026-87697 dotnet: dotnet: arbitrary code execution via untrusted data deserialization
Deserialization of untrusted data in .NET allows an unauthorized attacker to execute code over a network.
Affected products:
- .NET Windows Desktop Runtime (release 9.0): 9.0.0 - 9.0.20; fixed 9.0.21
- .NET Windows Desktop Runtime (release 11.0): 11.0.0-preview.1 - 11.0.0-rc.1; fixed 11.0.0-rc.2
- .NET Windows Desktop Runtime (release 8.0): 8.0.0 - 8.0.31; fixed 8.0.32
- .NET Windows Desktop Runtime (release 10.0): 10.0.0 - 10.0.12; fixed 10.0.13
2026-10-13
Published