RHSA-2026:94109 - Security Advisory

Topic

An update for kernel is now available for Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions.

Red Hat Product Security has rated this update as having a security impact of Critical. 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

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change (CVE-2025-71066)
• kernel: HID: wacom: fix out-of-bounds read in wacom_intuos_bt_irq (CVE-2026-43051)
• kernel: net: bridge: use a stable FDB dst snapshot in RCU readers (CVE-2026-46086)
• kernel: Bluetooth: hci_ldisc: Clear HCI_UART_PROTO_INIT on error (CVE-2026-53073)
• kernel: sctp: validate embedded INIT chunk and address list lengths in cookie (CVE-2026-53224)
• kernel: sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing (CVE-2026-53246)
• kernel: arm64: tlb: Flush walk cache when unsharing PMD tables (CVE-2026-63875)
• kernel: scsi: libiscsi_tcp: Bound SCSI Response data segment to the connection buffer (CVE-2026-74556)
• kernel: nvme/ioctl: check SUBMIT_IO with nvme_cmd_allowed() (CVE-2026-90227)
• kernel: ipv4: free inet_opt and ireq_opt after an RCU grace period (CVE-2026-98432)
• kernel: ZDI-CAN-33367: Linux Kernel skbuff skb_zerocopy Improper Ownership Management Local Privilege Escalation Vulnerability ()

Bug Fix(es) and Enhancement(s):

• The Kernel panic occurred at strlen+0x0 because a race event filter treats the user space pointer as a normal pointer [rhel-9.4.z] (JIRA:RHEL-291139)
• kernel: intel_powerclamp cur_state write triggers NULL-pointer dereference / panic [rhel-9.4.z] (JIRA:RHEL-293259)

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

The system must be rebooted for this update to take effect.

Red Hat recommends treating all kernel errata as security-relevant. Given the kernel's fundamental role, any bug has a higher chance of impacting system security, even if that impact only becomes clear after a fix is published. Therefore, Red Hat prioritizes delivering fixes that improve our customers' overall security posture.

Because of this proactive approach, a patch may be associated with a CVE assignment at a future date. Retroactive CVE assignments are always documented in the corresponding errata and on Red Hat's CVE pages. We strongly advise against delaying updates, as doing so may leave your system exposed when protections are already available.

Affected Products

• Red Hat Enterprise Linux Server - AUS 9.4 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.4 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.4 x86_64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.4 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.4 s390x
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.4 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.4 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.4 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.4 s390x

Fixes

• BZ - 2429036 - CVE-2025-71066 kernel: net/sched: ets: Always remove class from active list before deleting in ets_qdisc_change
• BZ - 2464462 - CVE-2026-43051 kernel: HID: wacom: fix out-of-bounds read in wacom_intuos_bt_irq
• BZ - 2481989 - CVE-2026-46086 kernel: net: bridge: use a stable FDB dst snapshot in RCU readers
• BZ - 2492447 - CVE-2026-53073 kernel: Bluetooth: hci_ldisc: Clear HCI_UART_PROTO_INIT on error
• BZ - 2492769 - CVE-2026-53224 kernel: sctp: validate embedded INIT chunk and address list lengths in cookie
• BZ - 2492771 - CVE-2026-53246 kernel: sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing
• BZ - 2502318 - CVE-2026-63875 kernel: arm64: tlb: Flush walk cache when unsharing PMD tables
• BZ - 2517010 - CVE-2026-74556 kernel: scsi: libiscsi_tcp: Bound SCSI Response data segment to the connection buffer
• BZ - 2536346 - CVE-2026-90227 kernel: nvme/ioctl: check SUBMIT_IO with nvme_cmd_allowed()
• BZ - 2553390 - CVE-2026-98432 kernel: ipv4: free inet_opt and ireq_opt after an RCU grace period
• BZ - 2559835 - kernel: ZDI-CAN-33367: Linux Kernel skbuff skb_zerocopy Improper Ownership Management Local Privilege Escalation Vulnerability

CVEs

• CVE-2025-71066
• CVE-2026-43051
• CVE-2026-46086
• CVE-2026-53073
• CVE-2026-53224
• CVE-2026-53246
• CVE-2026-63875
• CVE-2026-74556
• CVE-2026-90227
• CVE-2026-98432

References

• https://access.redhat.com/security/updates/classification/#critical