UBUNTU-CVE-2026-109475: High severity ubuntu/dotnet6 vulnerability

Q: Which systems are exposed to this issue?

Systems using Managed HttpListener in Ubuntu packages for dotnet6, dotnet8, dotnet10, or dotnet11 are implicated. The issue is remotely reachable and requires no authentication or user interaction.

Q: What does an attacker need to do to trigger the denial of service?

An attacker needs to send an unterminated HTTP request line to a vulnerable Managed HttpListener. Processing can recurse until the process stack is exhausted, causing a denial of service.

Published Nov 10, 2026

Updated

Managed HttpListener can recursively process an unterminated request line and exhaust the process stack.

Affected Software

7 affected componentsFixes available

ubuntu/dotnet6*

ubuntu/dotnet8<8.0.134-8.0.34-0ubuntu1~22.04.1

8.0.134-8.0.34-0ubuntu1~22.04.1

ubuntu/dotnet10<10.0.115-10.0.15-0ubuntu1~24.04.1

10.0.115-10.0.15-0ubuntu1~24.04.1

ubuntu/dotnet8<8.0.134-8.0.34-0ubuntu1~24.04.1

8.0.134-8.0.34-0ubuntu1~24.04.1

ubuntu/dotnet10<10.0.115-10.0.15-0ubuntu1~26.10.1

10.0.115-10.0.15-0ubuntu1~26.10.1

ubuntu/dotnet11<11.0.100-11.0.0-0ubuntu1~26.10.1

11.0.100-11.0.0-0ubuntu1~26.10.1

ubuntu/dotnet10<10.0.115-10.0.15-0ubuntu1~26.04.1

10.0.115-10.0.15-0ubuntu1~26.04.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/dotnet8 to a version that resolves this vulnerability.
Fixed in 8.0.134-8.0.34-0ubuntu1~22.04.1
Upgrade
Upgrade ubuntu/dotnet10 to a version that resolves this vulnerability.
Fixed in 10.0.115-10.0.15-0ubuntu1~24.04.1
Upgrade
Upgrade ubuntu/dotnet8 to a version that resolves this vulnerability.
Fixed in 8.0.134-8.0.34-0ubuntu1~24.04.1
Upgrade
Upgrade ubuntu/dotnet10 to a version that resolves this vulnerability.
Fixed in 10.0.115-10.0.15-0ubuntu1~26.10.1
Upgrade
Upgrade ubuntu/dotnet11 to a version that resolves this vulnerability.
Fixed in 11.0.100-11.0.0-0ubuntu1~26.10.1
Upgrade
Upgrade ubuntu/dotnet10 to a version that resolves this vulnerability.
Fixed in 10.0.115-10.0.15-0ubuntu1~26.04.1

Event History

Nov 10, 2026

CVE Published

via OSV·12:00 AM

Data Sourced

via OSV·12:00 AM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are exposed to this issue?

Systems using Managed HttpListener in Ubuntu packages for dotnet6, dotnet8, dotnet10, or dotnet11 are implicated. The issue is remotely reachable and requires no authentication or user interaction.

What does an attacker need to do to trigger the denial of service?