Red Hat Security Advisory: kernel-rt 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: net/sched: Make cake_enqueue return NET_XMIT_CN when past buffer_limit (CVE-2025-39766) * kernel: Linux kernel: Use-after-free in traffic control (act_ct) may lead to denial of service or privilege escalation (CVE-2026-23270) * kernel: Linux kernel: Use-after-free in bonding driver leads to denial of service (CVE-2026-31419) * kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() (CVE-2026-43037) * kernel: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() (CVE-2026-43038) * kernel: smb: client: validate the whole DACL before rewriting it in cifsacl (CVE-2026-31709) * kernel: md/bitmap: fix GPF in write_page caused by resize race (CVE-2026-43163) 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 covers several security fixes in the Linux kernel packages provided by Red Hat, including CVE-2025-39766 where the net/sched subsystem's cake_enqueue function is modified to return NET_XMIT_CN when past buffer_limit, and other use-after-free vulnerabilities in traffic control and bonding drivers (CVE-2026-23270, CVE-2026-31419). Additional fixes address issues in IPv6 tunneling, SMB client DACL validation, and md/bitmap race conditions. These vulnerabilities impact multiple kernel subsystems and architectures across Red Hat Enterprise Linux 10 and related products. The advisory confirms patch availability and recommends updating to fixed kernel versions.
Potential Impact
The vulnerabilities could allow an attacker to cause denial of service or escalate privileges on affected systems by exploiting use-after-free conditions and improper buffer handling in kernel networking and driver components. The issues affect core kernel functionality, potentially impacting system stability and security.
Mitigation Recommendations
A security update is available from Red Hat and should be applied promptly. The update requires a system reboot to take effect. Users should upgrade to the fixed kernel versions as specified in the Red Hat advisory RHSA-2026:9264. No additional mitigation steps are indicated beyond applying the official patch and rebooting.
Red Hat Security Advisory: kernel-rt 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: net/sched: Make cake_enqueue return NET_XMIT_CN when past buffer_limit (CVE-2025-39766) * kernel: Linux kernel: Use-after-free in traffic control (act_ct) may lead to denial of service or privilege escalation (CVE-2026-23270) * kernel: Linux kernel: Use-after-free in bonding driver leads to denial of service (CVE-2026-31419) * kernel: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() (CVE-2026-43037) * kernel: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() (CVE-2026-43038) * kernel: smb: client: validate the whole DACL before rewriting it in cifsacl (CVE-2026-31709) * kernel: md/bitmap: fix GPF in write_page caused by resize race (CVE-2026-43163) 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
This advisory covers several security fixes in the Linux kernel packages provided by Red Hat, including CVE-2025-39766 where the net/sched subsystem's cake_enqueue function is modified to return NET_XMIT_CN when past buffer_limit, and other use-after-free vulnerabilities in traffic control and bonding drivers (CVE-2026-23270, CVE-2026-31419). Additional fixes address issues in IPv6 tunneling, SMB client DACL validation, and md/bitmap race conditions. These vulnerabilities impact multiple kernel subsystems and architectures across Red Hat Enterprise Linux 10 and related products. The advisory confirms patch availability and recommends updating to fixed kernel versions.
Potential Impact
The vulnerabilities could allow an attacker to cause denial of service or escalate privileges on affected systems by exploiting use-after-free conditions and improper buffer handling in kernel networking and driver components. The issues affect core kernel functionality, potentially impacting system stability and security.
Mitigation Recommendations
A security update is available from Red Hat and should be applied promptly. The update requires a system reboot to take effect. Users should upgrade to the fixed kernel versions as specified in the Red Hat advisory RHSA-2026:9264. No additional mitigation steps are indicated 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-2026:9264
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-68741"]
Threat ID: 6a175eede29bf47b50edbf3d
Added to database: 05/27/2026, 21:15:25 UTC
Last enriched: 08/11/2026, 20:36:27 UTC
Last updated: 09/25/2026, 01:47:39 UTC
Views: 122
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