CVE-2026-70179: high-severity vulnerability in Microsoft.AspNetCore.Authentication.Negotiate
ASP.NET Core Elevation of Privilege Vulnerability
Published · Updated
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.6%
exploitation probability
0.6%top 55% of all CVEs
observed exploitation
nono source reports it
Authentication bypass by spoofing in ASP.NET Core allows an authorized attacker to elevate privileges over a network.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Affected products
Microsoft · Microsoft.AspNetCore.Authentication.NegotiateMicrosoft · Microsoft Visual Studio 2022 version 17.14Microsoft · Microsoft Visual Studio 2026 version 18.10Related CVEs — Microsoft.AspNetCore.Authentication.Negotiate
In the same product, most dangerous first.
CVE-2025-55315CRITICALASP.NET Security Feature Bypass VulnerabilityEPSS 65.9%CVE-2025-47959HIGHVisual Studio Remote Code Execution VulnerabilityEPSS 10.9%CVE-2026-50646HIGH.NET Framework Remote Code Execution VulnerabilityEPSS 4.0%CVE-2025-53773HIGHGitHub Copilot and Visual Studio Remote Code Execution VulnerabilityEPSS 3.2%CVE-2026-32203HIGH.NET and Visual Studio Denial of Service VulnerabilityEPSS 2.4%CVE-2026-32178HIGH.NET Spoofing VulnerabilityEPSS 2.1%