Red Hat Security Advisory: .NET 8.0 security update
.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 8.0.127 and .NET Runtime 8.0.27.Security Fix(es): * serialize-javascript: serialize-javascript: Denial of Service via specially crafted array-like object serialization (CVE-2026-34043) * dotnet: .NET: infinite loop allows an attacker to cause a denial of service (CVE-2026-42899) 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.
AI Analysis
Technical Summary
This advisory addresses two denial of service vulnerabilities affecting .NET 8.0 on Red Hat Enterprise Linux 8. CVE-2026-34043 involves the serialize-javascript package, where specially crafted array-like objects can cause a denial of service during serialization. CVE-2026-42899 is an infinite loop vulnerability in .NET that can also cause denial of service. Red Hat has released updated packages: .NET SDK 8.0.127 and .NET Runtime 8.0.27 to remediate these issues. The advisory covers multiple architectures including x86_64, s390x, ppc64le, and aarch64. No CVSS scores are provided in the advisory, but the severity is rated as important by Red Hat. There are no known exploits in the wild at this time.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions on affected systems running .NET 8.0 by triggering infinite loops or resource exhaustion during serialization. This could disrupt applications relying on .NET, leading to service unavailability. There is no indication of privilege escalation or code execution impacts. No active exploitation is currently known.
Mitigation Recommendations
Red Hat has released official updates that fix these vulnerabilities in .NET SDK 8.0.127 and .NET Runtime 8.0.27. Users should apply these updates promptly to remediate the denial of service issues. Detailed update instructions are available in the Red Hat advisory and knowledge base article https://access.redhat.com/articles/11258. No additional mitigation or workarounds are specified by the vendor.
Red Hat Security Advisory: .NET 8.0 security update
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 8.0.127 and .NET Runtime 8.0.27.Security Fix(es): * serialize-javascript: serialize-javascript: Denial of Service via specially crafted array-like object serialization (CVE-2026-34043) * dotnet: .NET: infinite loop allows an attacker to cause a denial of service (CVE-2026-42899) 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.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory addresses two denial of service vulnerabilities affecting .NET 8.0 on Red Hat Enterprise Linux 8. CVE-2026-34043 involves the serialize-javascript package, where specially crafted array-like objects can cause a denial of service during serialization. CVE-2026-42899 is an infinite loop vulnerability in .NET that can also cause denial of service. Red Hat has released updated packages: .NET SDK 8.0.127 and .NET Runtime 8.0.27 to remediate these issues. The advisory covers multiple architectures including x86_64, s390x, ppc64le, and aarch64. No CVSS scores are provided in the advisory, but the severity is rated as important by Red Hat. There are no known exploits in the wild at this time.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions on affected systems running .NET 8.0 by triggering infinite loops or resource exhaustion during serialization. This could disrupt applications relying on .NET, leading to service unavailability. There is no indication of privilege escalation or code execution impacts. No active exploitation is currently known.
Mitigation Recommendations
Red Hat has released official updates that fix these vulnerabilities in .NET SDK 8.0.127 and .NET Runtime 8.0.27. Users should apply these updates promptly to remediate the denial of service issues. Detailed update instructions are available in the Red Hat advisory and knowledge base article https://access.redhat.com/articles/11258. No additional mitigation or workarounds are specified by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:21291
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-42899"]
- State
- PUBLISHED
Threat ID: 6a18ab6fe29bf47b50288354
Added to database: 05/28/2026, 20:54:07 UTC
Last enriched: 08/10/2026, 20:17:52 UTC
Last updated: 09/14/2026, 22:01:33 UTC
Views: 104
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