CVE-2026-50528: Microsoft Security Advisory CVE-2026-50528 – .NET Security Feature Bypass Vulnerability

Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET TLS/SSL (System.Net.Security). This advisory also provides guidance on what developers can do to updat…

8.2CVSS Score

HIGHSeverity

NOCISA KEV

0.4%EPSS Score

VulnerabilityImpact Type

📋 Vulnerability Details

CVE ID	CVE-2026-50528
Vendor	nuget
Affected Product	Microsoft.NetCore.App.Runtime.linux-arm
Vulnerability Type	Vulnerability
CVSS Score	8.2 (HIGH)
EPSS Score	0.4% probability of exploitation in the next 30 days
Actively Exploited	❌ No known exploitation
Patch Status	See Vendor Advisory →
Reported By	CYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories)

🔬 Technical Analysis

Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET TLS/SSL (System.Net.Security). This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. A security feature bypass vulnerability exists in .NET 8, .NET 9, and .NET 10 when processing TLS/SSL connections. An attacker can exploit the SslStream implementation to bypass authorization checks during secure communication.

Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/TBD

CVSS Details - Version: 3.1

• Severity: High

• Score: 8.2

• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N

• Weakness: CWE-863 (Incorrect Authorization)

🎯 Known Indicators of Compromise

{"type":"url","value":"https://github.com/dotnet/announcements/issues/**TBD**","confidence_score":0.82,"first_seen":"2026-07-20","source_count":1} {"type":"domain","value":"system.net","confidence_score":0.75,"first_seen":"2026-07-20","source_count":1}

📚 Advisory References

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