RHSA-2026:41899 - Security Advisory

Topic

An update for .NET 9.0 is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

.NET is a managed-software framework. It implements a subset of the .NET framework APIs and several new APIs, and it includes a CLR implementation.

New versions of .NET that address a security vulnerability are now available. The updated versions are .NET SDK 9.0.119 and .NET Runtime 9.0.18.

Security Fix(es):

• dotnet: SocketsHttpHandler Http2Connection - HTTP/2 SETTINGS/PING ACK flood causing OOM (CVE-2026-50651)
• dotnet: .NET Core: Denial of Service via type confusion (CVE-2026-57108)
• ASP.NET Core: ASP.NET Core: Denial of Service via uncontrolled resource allocation (CVE-2026-56170)
• ASP.NET Core: ASP.NET Core: Privilege Escalation via Incorrect Authentication Algorithm (CVE-2026-47300)
• ASP.NET Core: ASP.NET Core: Privilege Elevation via Authentication Bypass (CVE-2026-47303)
• dotnet: .NET Security Feature Bypass Vulnerability (CVE-2026-47304)
• dotnet: .NET: Denial of Service vulnerability due to uncontrolled resource allocation (CVE-2026-47302)
• dotnet: .NET Framework: Privilege escalation via code injection (CVE-2026-50650)
• dotnet: .NET: Security feature bypass due to incorrect authorization (CVE-2026-50528)
• dotnet: .NET: Local code execution via deserialization of untrusted data (CVE-2026-50649)
• dotnet: .NET: Local tampering via improper link resolution (CVE-2026-50526)
• dotnet: .NET Framework: Local Code Execution via Protection Mechanism Failure (CVE-2026-50646)
• dotnet: .NET: Denial of Service due to uncontrolled resource allocation (CVE-2026-50525)
• dotnet: .NET Framework: Denial of Service via network-based buffer overflow (CVE-2026-50527)
• dotnet: .NET Framework: Remote Denial of Service due to uncontrolled resource allocation (CVE-2026-50648)
• .NET: .NET: Network Spoofing Vulnerability (CVE-2026-50659)
• dotnet: .NET Framework: Denial of Service via improper input validation (CVE-2026-50524)

Bug Fix(es) and Enhancement(s):

• Update .NET 9.0 to SDK 9.0.119 and Runtime 9.0.18 (JIRA:RHEL-192469)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for x86_64 8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 8 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 8 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 8.10 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 8.10 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 8.10 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 8.10 s390x

Fixes

• BZ - 2499217 - CVE-2026-50651 dotnet: SocketsHttpHandler Http2Connection - HTTP/2 SETTINGS/PING ACK flood causing OOM
• BZ - 2500109 - CVE-2026-57108 dotnet: .NET Core: Denial of Service via type confusion
• BZ - 2500189 - CVE-2026-56170 ASP.NET Core: ASP.NET Core: Denial of Service via uncontrolled resource allocation
• BZ - 2500492 - CVE-2026-47300 ASP.NET Core: ASP.NET Core: Privilege Escalation via Incorrect Authentication Algorithm
• BZ - 2500502 - CVE-2026-47303 ASP.NET Core: ASP.NET Core: Privilege Elevation via Authentication Bypass
• BZ - 2500509 - CVE-2026-47304 dotnet: .NET Security Feature Bypass Vulnerability
• BZ - 2500515 - CVE-2026-47302 dotnet: .NET: Denial of Service vulnerability due to uncontrolled resource allocation
• BZ - 2500556 - CVE-2026-50650 dotnet: .NET Framework: Privilege escalation via code injection
• BZ - 2500562 - CVE-2026-50528 dotnet: .NET: Security feature bypass due to incorrect authorization
• BZ - 2500563 - CVE-2026-50649 dotnet: .NET: Local code execution via deserialization of untrusted data
• BZ - 2500565 - CVE-2026-50526 dotnet: .NET: Local tampering via improper link resolution
• BZ - 2500577 - CVE-2026-50646 dotnet: .NET Framework: Local Code Execution via Protection Mechanism Failure
• BZ - 2500580 - CVE-2026-50525 dotnet: .NET: Denial of Service due to uncontrolled resource allocation
• BZ - 2500581 - CVE-2026-50527 dotnet: .NET Framework: Denial of Service via network-based buffer overflow
• BZ - 2500587 - CVE-2026-50648 dotnet: .NET Framework: Remote Denial of Service due to uncontrolled resource allocation
• BZ - 2500593 - CVE-2026-50524 dotnet: .NET Framework: Denial of Service via improper input validation

CVEs

• CVE-2026-47300
• CVE-2026-47302
• CVE-2026-47303
• CVE-2026-47304
• CVE-2026-50524
• CVE-2026-50525
• CVE-2026-50526
• CVE-2026-50527
• CVE-2026-50528
• CVE-2026-50646
• CVE-2026-50648
• CVE-2026-50649
• CVE-2026-50650
• CVE-2026-50651
• CVE-2026-50659
• CVE-2026-56170
• CVE-2026-57108

References

• https://access.redhat.com/security/updates/classification/#important