Red Hat Security Advisory: kernel security update
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * 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 security advisory RHSA-2026:9515 reports two kernel vulnerabilities affecting Red Hat Enterprise Linux 8.8. CVE-2026-23204 fixes an issue in the net/sched cls_u32 component by using skb_header_pointer_careful(). CVE-2026-23231 addresses a use-after-free vulnerability in nf_tables_addchain that could allow privilege escalation or denial of service. The advisory rates the update as having moderate security impact and provides updated kernel packages to remediate these issues.
Potential Impact
The vulnerabilities impact the Linux kernel core in Red Hat Enterprise Linux 8.8. CVE-2026-23204 affects network scheduling functionality, potentially impacting confidentiality and availability. CVE-2026-23231 could allow a local attacker with limited privileges to escalate privileges or cause a denial of service via a use-after-free condition. The CVSS vector for CVE-2026-23204 indicates local attack vector, low attack complexity, low privileges required, no user interaction, unchanged scope, high confidentiality impact, no integrity impact, and high availability impact. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for Red Hat Enterprise Linux 8.8 that addresses these vulnerabilities. Users should apply the kernel update as described in Red Hat advisory RHSA-2026:9515 and reboot affected systems to ensure the fixes take effect. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the official patch and rebooting.
Red Hat Security Advisory: kernel security update
Description
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * 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.
CVSS v3.1
Score 7.1high
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Red Hat security advisory RHSA-2026:9515 reports two kernel vulnerabilities affecting Red Hat Enterprise Linux 8.8. CVE-2026-23204 fixes an issue in the net/sched cls_u32 component by using skb_header_pointer_careful(). CVE-2026-23231 addresses a use-after-free vulnerability in nf_tables_addchain that could allow privilege escalation or denial of service. The advisory rates the update as having moderate security impact and provides updated kernel packages to remediate these issues.
Potential Impact
The vulnerabilities impact the Linux kernel core in Red Hat Enterprise Linux 8.8. CVE-2026-23204 affects network scheduling functionality, potentially impacting confidentiality and availability. CVE-2026-23231 could allow a local attacker with limited privileges to escalate privileges or cause a denial of service via a use-after-free condition. The CVSS vector for CVE-2026-23204 indicates local attack vector, low attack complexity, low privileges required, no user interaction, unchanged scope, high confidentiality impact, no integrity impact, and high availability impact. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for Red Hat Enterprise Linux 8.8 that addresses these vulnerabilities. Users should apply the kernel update as described in Red Hat advisory RHSA-2026:9515 and reboot affected systems to ensure the fixes take effect. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the official patch and rebooting.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:9515
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-23231"]
- Cvss Version
- 3.1
Threat ID: 6a27e9fd8dd33fbd8517cfb2
Added to database: 06/09/2026, 10:25:01 UTC
Last enriched: 07/12/2026, 10:19:57 UTC
Last updated: 07/31/2026, 19:24:49 UTC
Views: 98
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