CVE-2026-84008
published 2026-10-13CVE-2026-84008: Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
PriorityP346high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.99%
62.3th percentile
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
Affected
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_net_framework_3.5 | >= 3.5.0 < 2.0.50727.9188 AND 3.0.30729.9171 | 2.0.50727.9188 AND 3.0.30729.9171 |
| microsoft | microsoft_net_framework_3.5_and_4.6.2_4.7_4.7.1_4.7.2 | >= 3.0.0.0 < 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 |
| microsoft | microsoft_net_framework_3.5_and_4.7.2 | >= 4.7.0 < 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 |
| microsoft | microsoft_net_framework_3.5_and_4.8 | >= 4.8.0 < 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 |
| microsoft | microsoft_net_framework_3.5_and_4.8.1 | >= 4.8.1 < 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 | 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 |
| microsoft | microsoft_net_framework_4.6.2_4.7_4.7.1_4.7.2 | >= 4.7.0 < 4.7.4150.0 | 4.7.4150.0 |
| microsoft | microsoft_net_framework_4.8 | >= 4.8.0 < 4.8.4811.0 | 4.8.4811.0 |
| microsoft | microsoft_net_framework_4.8.1 | >= 4.8.0.0 < 4.8.9363.0 | 4.8.9363.0 |
| 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 | system.security.cryptography.pkcs | >= 10.0.0 < 10.0.13 | 10.0.13 |
| microsoft | system.security.cryptography.pkcs | >= 10.0.0 < 10.0.13 | 10.0.13 |
| microsoft | system.security.cryptography.pkcs | >= 11.0.0-preview.1 < 11.0.0-rc.2 | 11.0.0-rc.2 |
| microsoft | system.security.cryptography.pkcs | >= 8.0.0 < 8.0.2 | 8.0.2 |
| microsoft | system.security.cryptography.pkcs | >= 9.0.0 < 9.0.21 | 9.0.21 |
| ubuntu | dotnet10 | — | — |
| ubuntu | dotnet11 | — | — |
| ubuntu | dotnet8 | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
ghsa7.5HIGH
vendor_redhat7.5HIGH
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Ubuntu
.NET vulnerabilities
vendor_ubuntu·2026-10-20
CVE-2026-70188 .NET vulnerabilities
Title: .NET vulnerabilities
Summary: Several security issues were fixed in .NET.
Multiple security issues were discovered in .NET and this update includes
new upstream .NET versions to fix these issues.
.NET 8 has been updated to 8.0.32 in Ubuntu 22.04 LTS and Ubuntu 24.04 LTS.
.NET 10 has been updated to 10.0.13 in Ubuntu 24.04 LTS, Ubuntu 26.04 LTS
and Ubuntu 26.10. .NET 11 has been updated to 11.0.0~rc2 in Ubuntu 26.10.
In addition to security fixes, the updated packages contain bug fixes, new
features, and possibly incompatible changes.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
dotnet: .NET Denial of Service Vulnerability
vendor_redhat·2026-10-13·CVSS 7.5
CVE-2026-84008 [HIGH] CWE-1333 dotnet: .NET Denial of Service Vulnerability
dotnet: .NET Denial of Service Vulnerability
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
A flaw was found in .NET. Due to inefficient algorithmic complexity, an unauthorized remote attacker can send specially crafted requests over the network to cause excessive resource consumption. This issue can result in a Denial of Service (DoS), rendering the affected application unresponsive to legitimate users.
Statement: A flaw was found in .NET caused by inefficient algorithmic complexity. An unauthenticated remote attacker could exploit this vulnerability by sending specially crafted network requests to an application running on an affected .NET runtime or framework component. Processing these requests triggers excessive CPU or mem
VulDB
Microsoft .NET System.Security.Cryptography.Pkcs SignedCms.CheckSignature algorithmic complexity
vuldb·2026-10-14·CVSS 7.5
CVE-2026-84008 [HIGH] Microsoft .NET System.Security.Cryptography.Pkcs SignedCms.CheckSignature algorithmic complexity
A vulnerability, which was classified as problematic, has been found in Microsoft .NET. Impacted is the function SignedCms.CheckSignature of the component System.Security.Cryptography.Pkcs. This manipulation causes inefficient algorithmic complexity.
This vulnerability is handled as CVE-2026-84008. The attack can be initiated remotely. There is not any exploit available.
It is recommended to apply a patch to fix this issue.
GHSA
Microsoft Security Advisory CVE-2026-84008 - .NET Denial of Service Vulnerability
ghsa·2026-10-13·CVSS 7.5
CVE-2026-84008 [HIGH] CWE-407 Microsoft Security Advisory CVE-2026-84008 - .NET Denial of Service Vulnerability
Microsoft Security Advisory CVE-2026-84008 - .NET Denial of Service Vulnerability
## Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in System.Security.Cryptography.Pkcs. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
`SignedCms.CheckSignature` can repeatedly reparse attacker-controlled X.509 data, causing unauthenticated quadratic CPU exhaustion.
## Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/468
## CVSS Details
- **Version:** 3.1
- **Severity:** High
- **Score:** 7.5
- **Vector:** `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`
- **Weakness:** CWE-407 (Inefficient Algorithmic Complexity)
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-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-rawhide]
bugzilla·2026-10-23·CVSS 7.5
CVE-2026-84008 [HIGH] CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-rawhide]
CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-rawhide]
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.
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
Bugzilla
CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-43]
bugzilla·2026-10-23·CVSS 7.5
CVE-2026-84008 [HIGH] CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-43]
CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [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.
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
Bugzilla
CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-44]
bugzilla·2026-10-23·CVSS 7.5
CVE-2026-84008 [HIGH] CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-44]
CVE-2026-84008 dotnet10.0: .NET Denial of Service Vulnerability [fedora-44]
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.
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
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-2026-84008 dotnet: .NET Denial of Service Vulnerability
bugzilla·2026-10-13·CVSS 7.5
CVE-2026-84008 [HIGH] CVE-2026-84008 dotnet: .NET Denial of Service Vulnerability
CVE-2026-84008 dotnet: .NET Denial of Service Vulnerability
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
Affected packages:
- System.Security.Cryptography.Pkcs (release 9.0): 9.0.0 - 9.0.20; fixed 9.0.21
- System.Security.Cryptography.Pkcs (release 11.0): 11.0.0-preview.1 - 11.0.0-rc.1; fixed 11.0.0-rc.2
- System.Security.Cryptography.Pkcs (release 10.0): 10.0.0 - 10.0.12; fixed 10.0.13
- System.Security.Cryptography.Pkcs (release 8.0): 8.0.0 - 8.0.1; fixed 8.0.2
2026-10-13
Published