ESB-2026.4609

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.4609 .NET 9.0 security update 5 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: .NET 9.0 Publisher: Red Hat Operating System: Red Hat Resolution: Patch/Upgrade CVE Names: CVE-2026-26171 CVE-2026-32178 CVE-2026-32203 CVE-2026-33116 Original Bulletin: https://access.redhat.com/errata/RHSA-2026:13280 Comment: CVSS (Max): 7.5 CVE-2026-33116 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) CVSS Source: Red Hat Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H EPSS (Max): 0.8% (73rd) CVE-2026-33116 2026-05-03 - --------------------------BEGIN INCLUDED TEXT-------------------- RHSA-2026:13280 - Security Advisory Issued: 2026-05-04 Updated: 2026-05-04 Synopsis .net 9.0 security update Type/Severity Security Advisory: Important Topic An update for .NET 9.0 is now available for Red Hat Enterprise Linux 10.0 Extended Update Support. 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 9.0.116 and .NET Runtime 9.0.15.Security Fix (es): o dotnet: .NET: Security Bypass and Denial of Service Vulnerability (CVE-2026-26171) o dotnet: .NET: Denial of Service via stack overflow (CVE-2026-32203) o dotnet: .NET: Denial of Service via Infinite Recursion in XmlDecryptionTransform (CVE-2026-33116) o dotnet: Dotnet: SMTP Command Injection and Header Injection via MailAddress parsing flaw (CVE-2026-32178) 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 o Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.0 x86_64 o Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0 s390x o Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0 ppc64le o Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0 aarch64 o Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 10.0 x86_64 o Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 10.0 ppc64le o Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 10.0 s390x o Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 10.0 aarch64 o Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0 aarch64 o Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0 s390x o Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0 ppc64le o Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0 x86_64 Fixes o BZ - 2457739 - CVE-2026-26171 dotnet: .NET: Security Bypass and Denial of Service Vulnerability o BZ - 2457740 - CVE-2026-32203 dotnet: .NET: Denial of Service via stack overflow o BZ - 2457741 - CVE-2026-33116 dotnet: .NET: Denial of Service via Infinite Recursion in XmlDecryptionTransform o BZ - 2457781 - CVE-2026-32178 dotnet: Dotnet: SMTP Command Injection and Header Injection via MailAddress parsing flaw CVEs o CVE-2026-26171 o CVE-2026-32178 o CVE-2026-32203 o CVE-2026-33116 References o https://access.redhat.com/security/updates/classification/#important - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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