Red Hat Security Advisory: kernel security update

Fixed packages 71

Vulnerabilities 7

• 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
• 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 7.8
  CVE-2026-23270

  net/sched: Only allow act_ct to bind to clsact/ingress qdiscs and shared blocks

  In the Linux kernel, the following vulnerability has been resolved: net/sched: Only allow act_ct to bind to clsact/ingress qdiscs and shared blocks As Paolo said earlier [1]: "Since the blamed commit below, classify can return TC_ACT_CONSUMED while the curren…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  Mar 18, 2026
• High 7.8
  CVE-2026-31419

  net: bonding: fix use-after-free in bond_xmit_broadcast()

  In the Linux kernel, the following vulnerability has been resolved: net: bonding: fix use-after-free in bond_xmit_broadcast() bond_xmit_broadcast() reuses the original skb for the last slave (determined by bond_is_last_slave()) and clones it for others. Concu…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Apr 13, 2026
• Unscored —
  CVE-2025-39766

  net/sched: Make cake_enqueue return NET_XMIT_CN when past buffer_limit

  In the Linux kernel, the following vulnerability has been resolved: net/sched: Make cake_enqueue return NET_XMIT_CN when past buffer_limit The following setup can trigger a WARNING in htb_activate due to the condition: !cl->leaf.q->q.qlen tc qdisc del dev lo …

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu Azure Linux
  Sep 11, 2025
• Unscored —
  CVE-2026-43163

  md/bitmap: fix GPF in write_page caused by resize race

  In the Linux kernel, the following vulnerability has been resolved: md/bitmap: fix GPF in write_page caused by resize race A General Protection Fault occurs in write_page() during array resize: RIP: 0010:write_page+0x22b/0x3c0 [md_mod] This is a use-after-fre…

  Linux Linux linux-raspi2 linux-hwe Linux Debian Ubuntu
  May 6, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2394648
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2448745
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2457829
• 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=2467059
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_22940.json
• report
  https://access.redhat.com/security/cve/CVE-2025-39766
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-39766
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-39766
• article
  https://lore.kernel.org/linux-cve-announce/2025091144-CVE-2025-39766-7465@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-23270
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-23270
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-23270
• article
  https://lore.kernel.org/linux-cve-announce/2026031847-CVE-2026-23270-cb9a@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-31419
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-31419
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-31419
• article
  https://lore.kernel.org/linux-cve-announce/2026041353-CVE-2026-31419-e176@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-31709
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-31709
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-31709
• article
  https://lore.kernel.org/linux-cve-announce/2026050122-CVE-2026-31709-335b@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-43037
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-43037
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-43037
• article
  https://lore.kernel.org/linux-cve-announce/2026050102-CVE-2026-43037-0346@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-43038
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-43038
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-43038
• article
  https://lore.kernel.org/linux-cve-announce/2026050103-CVE-2026-43038-b591@gregkh/T
• report
  https://access.redhat.com/security/cve/CVE-2026-43163
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-43163
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-43163
• article
  https://lore.kernel.org/linux-cve-announce/2026050632-CVE-2026-43163-86e1@gregkh/T