Red Hat Security Advisory: kernel security update
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: macvlan: fix possible UAF in macvlan_forward_source() (CVE-2026-23001) * kernel: net/sched: cls_u32: use skb_header_pointer_careful() (CVE-2026-23204) * kernel: kernel: Privilege escalation or denial of service via use-after-free in nf_tables_addchain() (CVE-2026-23231) 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
The Red Hat kernel-rt packages contain three security vulnerabilities: CVE-2026-23001 is a possible use-after-free in macvlan_forward_source(); CVE-2026-23204 involves the net/sched cls_u32 component where skb_header_pointer_careful() is now used to prevent issues; CVE-2026-23231 is a use-after-free in nf_tables_addchain() that can lead to privilege escalation or denial of service. These vulnerabilities affect the Real Time Linux Kernel enabling fine-tuning for high determinism systems. Red Hat has issued a security update (RHSA-2026:9835) for Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions to fix these issues. The update must be applied and the system rebooted for the fixes to take effect.
Potential Impact
The vulnerabilities include use-after-free conditions that may allow an attacker to escalate privileges or cause denial of service on affected systems running the kernel-rt packages. The impact is rated as moderate by Red Hat. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for the kernel-rt packages in Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions. Applying this update and rebooting the system is required to remediate these vulnerabilities. Refer to Red Hat's advisory RHSA-2026:9835 and the update instructions at https://access.redhat.com/articles/11258 for detailed guidance.
Red Hat Security Advisory: kernel security update
Description
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements. Security Fix(es): * kernel: macvlan: fix possible UAF in macvlan_forward_source() (CVE-2026-23001) * kernel: net/sched: cls_u32: use skb_header_pointer_careful() (CVE-2026-23204) * kernel: kernel: Privilege escalation or denial of service via use-after-free in nf_tables_addchain() (CVE-2026-23231) 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
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Red Hat kernel-rt packages contain three security vulnerabilities: CVE-2026-23001 is a possible use-after-free in macvlan_forward_source(); CVE-2026-23204 involves the net/sched cls_u32 component where skb_header_pointer_careful() is now used to prevent issues; CVE-2026-23231 is a use-after-free in nf_tables_addchain() that can lead to privilege escalation or denial of service. These vulnerabilities affect the Real Time Linux Kernel enabling fine-tuning for high determinism systems. Red Hat has issued a security update (RHSA-2026:9835) for Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions to fix these issues. The update must be applied and the system rebooted for the fixes to take effect.
Potential Impact
The vulnerabilities include use-after-free conditions that may allow an attacker to escalate privileges or cause denial of service on affected systems running the kernel-rt packages. The impact is rated as moderate by Red Hat. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for the kernel-rt packages in Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions. Applying this update and rebooting the system is required to remediate these vulnerabilities. Refer to Red Hat's advisory RHSA-2026:9835 and the update instructions at https://access.redhat.com/articles/11258 for detailed guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:9835
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-23204","CVE-2026-23231"]
- Cvss Version
- null
Threat ID: 6a27e9928dd33fbd851695b9
Added to database: 06/09/2026, 10:23:14 UTC
Last enriched: 07/12/2026, 10:19:31 UTC
Last updated: 07/31/2026, 19:24:47 UTC
Views: 58
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