Improper Encoding or Escaping of Output Affecting microsoft.aspnetcore.app.runtime.osx-arm64 package, versions [8.0.0-rc.1.23421.29,8.0.34)[9.0.0-preview.1.24081.5,9.0.23)[10.0.0-preview.1.25120.3,10.0.15)[11.0.0-preview.1.26104.118,11.0.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DOTNET-MICROSOFTASPNETCOREAPPRUNTIMEOSXARM64-22421703
- published11 Nov 2026
- disclosed9 Nov 2026
- creditRaffaello Tamagnini
Introduced: 9 Nov 2026
NewCVE-2026-109476 (opens in a new tab)How to fix?
Upgrade Microsoft.AspNetCore.App.Runtime.osx-arm64 to version 8.0.34, 9.0.23, 10.0.15, 11.0.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output when deriving cookie paths from PathBase, which does not percent-encode semicolons. An attacker can inject cookie path delimiters through a crafted X-Forwarded-Prefix header. This requires the application to honor forwarded-prefix headers and derive cookie paths from PathBase.