Important CVSS 5.9 2026-09 archive

Executive Summary

Improper handling of highly compressed data (data amplification) in ASP.NET Core allows an unauthorized attacker to deny service over a network.

Overview

5.9
CVSS MEDIUM
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Denial of Service
Released Sep 8 2026
Last Updated Sep 8 2026
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known

CVSS Vector

ATTACK VECTOR
Network
ATTACK COMPLEXITY
High
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
None
INTEGRITY
None
AVAILABILITY
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 5.2

EPSS Score

No EPSS score available for this CVE.

View on FIRST.org

Affected Products

9 affected products
Product KB Article Severity Impact Restart Required
.NET 10.0 installed on Windows 5126106 (Security Update) Important Denial of Service Maybe
.NET 8.0 installed on Windows 5126104 (Security Update) Important Denial of Service Maybe
.NET 9.0 installed on Windows 5126105 (Security Update) Important Denial of Service Maybe
ASP.NET Core 10.0 5126106 (Security Update) Important Denial of Service Yes
ASP.NET Core 11.0 (Security Update) Important Denial of Service Yes
ASP.NET Core 8.0 5126104 (Security Update) Important Denial of Service Yes
ASP.NET Core 9.0 5126105 (Security Update) Important Denial of Service Yes
Microsoft Visual Studio 2022 version 17.14 Release Notes (Security Update) Important Denial of Service Yes
Microsoft Visual Studio 2026 version 18.9 Release Notes (Security Update) Important Denial of Service Yes

Patches

5 patches
Article Type Restart
5126106 Security Update Maybe
5126104 Security Update Maybe
5126105 Security Update Maybe
Security Update Yes
Release Notes Security Update Yes

Exploits & PoC

Detection Rules

Acknowledgments

Anonymous
محمد السيد عثمان محمود القصاص