Red Hat Security Advisory: kernel security update

Fixed packages 124

Vulnerabilities 12

• Critical 9.8
  CVE-2026-43037

  ip6_tunnel: clear skb2->cb[] in ip4ip6_err()

  In the Linux kernel, the following vulnerability has been resolved: ip6_tunnel: clear skb2->cb[] in ip4ip6_err() Oskar Kjos reported the following problem. ip4ip6_err() calls icmp_send() on a cloned skb whose cb[] was written by the IPv6 receive path as struc…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  May 1, 2026
• Critical 9.8
  CVE-2026-43038

  ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach()

  In the Linux kernel, the following vulnerability has been resolved: ipv6: icmp: clear skb2->cb[] in ip6_err_gen_icmpv6_unreach() Sashiko AI-review observed: In ip6_err_gen_icmpv6_unreach(), the skb is an outer IPv4 ICMP error packet where its cb contains an I…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  May 1, 2026
• Critical 9.4
  CVE-2026-31685

  netfilter: ip6t_eui64: reject invalid MAC header for all packets

  In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_eui64: reject invalid MAC header for all packets `eui64_mt6()` derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 sour…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Apr 25, 2026
• High 8.8
  CVE-2026-31709

  smb: client: validate the whole DACL before rewriting it in cifsacl

  In the Linux kernel, the following vulnerability has been resolved: smb: client: validate the whole DACL before rewriting it in cifsacl build_sec_desc() and id_mode_to_cifs_acl() derive a DACL pointer from a server-supplied dacloffset and then use the incomin…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  May 1, 2026
• High 8.8
  CVE-2026-43110

  wifi: brcmfmac: validate bsscfg indices in IF events

  In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: validate bsscfg indices in IF events brcmf_fweh_handle_if_event() validates the firmware-provided interface index before it touches drvr->iflist[], but it still uses the raw b…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  May 6, 2026
• High 8.1
  CVE-2025-40135

  ipv6: use RCU in ip6_xmit()

  In the Linux kernel, the following vulnerability has been resolved: ipv6: use RCU in ip6_xmit() Use RCU in ip6_xmit() in order to use dst_dev_rcu() to prevent possible UAF.

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Nov 12, 2025
• High 8.1
  CVE-2025-40158

  ipv6: use RCU in ip6_output()

  In the Linux kernel, the following vulnerability has been resolved: ipv6: use RCU in ip6_output() Use RCU in ip6_output() in order to use dst_dev_rcu() to prevent possible UAF. We can remove rcu_read_lock()/rcu_read_unlock() pairs from ip6_finish_output2().

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Nov 12, 2025
• High 7.8
  CVE-2025-40170

  net: use dst_dev_rcu() in sk_setup_caps()

  In the Linux kernel, the following vulnerability has been resolved: net: use dst_dev_rcu() in sk_setup_caps() Use RCU to protect accesses to dst->dev from sk_setup_caps() and sk_dst_gso_max_size(). Also use dst_dev_rcu() in ip6_dst_mtu_maybe_forward(), and ip…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Nov 12, 2025
• High 7.8
  CVE-2025-68724

  crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id

  In the Linux kernel, the following vulnerability has been resolved: crypto: asymmetric_keys - prevent overflow in asymmetric_key_generate_id Use check_add_overflow() to guard against potential integer overflows when adding the binary blob lengths and the size…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Dec 24, 2025
• High 7.8
  CVE-2025-71089

  iommu: disable SVA when CONFIG_X86 is set

  In the Linux kernel, the following vulnerability has been resolved: iommu: disable SVA when CONFIG_X86 is set Patch series "Fix stale IOTLB entries for kernel address space", v7. This proposes a fix for a security vulnerability related to IOMMU Shared Virtual…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Jan 13, 2026
• High 7.8
  CVE-2026-23392

  netfilter: nf_tables: release flowtable after rcu grace period on error

  In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtabl…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Mar 25, 2026
• Unscored —
  CVE-2026-23216

  scsi: target: iscsi: Fix use-after-free in iscsit_dec_conn_usage_count()

  In the Linux kernel, the following vulnerability has been resolved: scsi: target: iscsi: Fix use-after-free in iscsit_dec_conn_usage_count() In iscsit_dec_conn_usage_count(), the function calls complete() while holding the conn->conn_usage_lock. As soon as co…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Feb 18, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2414506
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2414521
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2414523
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2424886
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2429104
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2440630
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2451218
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2461759
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2464351
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2464397
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2464476
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2467014
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_23237.json
• report
  https://access.redhat.com/security/cve/CVE-2025-40135
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-40135
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-40135
• article
  https://lore.kernel.org/linux-cve-announce/2025111255-CVE-2025-40135-67ca@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2025-40158
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-40158
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-40158
• article
  https://lore.kernel.org/linux-cve-announce/2025111258-CVE-2025-40158-4c9d@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2025-40170
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-40170
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-40170
• article
  https://lore.kernel.org/linux-cve-announce/2025111259-CVE-2025-40170-d39d@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2025-68724
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-68724
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-68724
• article
  https://lore.kernel.org/linux-cve-announce/2025122404-CVE-2025-68724-4d3c@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2025-71089
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-71089
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-71089
• article
  https://lore.kernel.org/linux-cve-announce/2026011341-CVE-2025-71089-a642@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-23216
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-23216
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-23216
• article
  https://lore.kernel.org/linux-cve-announce/2026021800-CVE-2026-23216-6c63@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-23392