RHSA-2026:27731HighCVSS 8.7

Red Hat Security Advisory: kernel security, bug fix, and enhancement update

Published
June 22, 2026
Last Modified
October 29, 2026

🔗 CVE IDs covered (14)

CVE-2025-40158 →CVE-2026-23136 →CVE-2026-31474 →CVE-2026-43501 →CVE-2026-45898 →CVE-2026-46323 →CVE-2025-30156 →CVE-2025-38154 →CVE-2025-40170 →CVE-2026-43116 →CVE-2026-46125 →CVE-2026-46227 →CVE-2026-46331 →CVE-2025-40135 →

📋 Description

CVE-2025-30156 — kernel: ceph: kernel: Ceph: exploit of hardcoded IVECs, in a misuse of AES, resulting in authentication bypass CVE-2025-38154 — kernel: Linux kernel: Use-after-free in BPF sockmap can lead to denial of service and privilege escalation CVE-2025-40135 — kernel: ipv6: use RCU in ip6_xmit() CVE-2025-40158 — kernel: ipv6: use RCU in ip6_output() CVE-2025-40170 — kernel: net: use dst_dev_rcu() in sk_setup_caps() CVE-2026-23136 — kernel: Linux kernel: Denial of Service in libceph OSD client due to unreset sparse-read state CVE-2026-31474 — kernel: can: isotp: fix tx.buf use-after-free in isotp_sendmsg() CVE-2026-43116 — kernel: netfilter: ctnetlink: ensure safe access to master conntrack CVE-2026-43501 — kernel: ipv6: rpl: reserve mac_len headroom when recompressed SRH grows CVE-2026-45898 — kernel: RDMA/iwcm: Fix workqueue list corruption by removing work_list CVE-2026-46125 — kernel: wifi: mac80211: remove station if connection prep fails CVE-2026-46227 — kernel: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL CVE-2026-46323 — kernel: Linux kernel: Use-After-Free in net/gro due to improper handling of zerocopy skbs CVE-2026-46331 — kernel: net/sched: act_pedit: extend the writable skb range per key

🎯 Affected products200

  • Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)
  • Red Hat Enterprise Linux Real Time EUS (v. 10.0)
  • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)
  • kernel-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-0:6.12.0-55.82.1.el10_0.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-0:6.12.0-55.82.1.el10_0.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-0:6.12.0-55.82.1.el10_0.src as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-0:6.12.0-55.82.1.el10_0.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-core-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-core-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-debug-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)
  • kernel-64k-debug-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux Real Time EUS (v. 10.0)
  • kernel-64k-debug-devel-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-debug-devel-matched-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-debug-modules-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-modules-core-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debug-modules-extra-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • kernel-64k-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)
  • kernel-64k-debuginfo-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux Real Time EUS (v. 10.0)
  • kernel-64k-devel-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-devel-matched-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • kernel-64k-modules-0:6.12.0-55.82.1.el10_0.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
  • +170 more not shown

✅ Remediation

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. Workaround: To mitigate this issue, Red Hat recommends isolating the Ceph messenger protocol to dedicated internal networks with strict access controls, limiting exposure to potential attackers. Administrators should audit and minimize the number of CephX client credentials in circulation and enforce strong credential management to reduce the risk of low-privilege key compromise. Where possible, deploy msgr2 with on-wire encryption to reduce passive sniffing exposure. It is strongly advised to apply vendor-supplied patches as soon as they are released, upgrade to fixed Ceph versions (Tentacle 20.2.4 or later), and rotate all CephX keys to the new AES-256-CTS-HMAC-SHA384-192 cipher type, prioritizing server-side keys. Workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Workaround: Systems which do not require it can blocklist the `can_isotp` module to prevent it from being loaded. See https://access.redhat.com/solutions/41278 for more information. Workaround: Mitigation for this issue is to skip loading the affected module "netfilter" onto the system till we have a fix available, this can be done by a blacklist mechanism, this will ensure the driver is not loaded at the boot time. ~~~ How do I blacklist a kernel module to prevent it from loading automatically? https://access.redhat.com/solutions/41278 ~~~ Workaround: To mitigate this issue, disable IPv6 Source Routing by setting the `accept_source_route` sysctl parameter to 0 for all IPv6 interfaces. This can prevent the kernel from processing IPv6 Source Routing Headers, thereby avoiding the vulnerable code path. To disable IPv6 Source Routing: `sysctl -w net.ipv6.conf.all.accept_source_route=0` `sysctl -w net.ipv6.conf.default.accept_source_route=0` To make this change persistent across reboots, add the following lines to `/etc/sysctl.d/99-disable-ipv6-srh.conf`: `net.ipv6.conf.all.accept_source_route = 0` `net.ipv6.conf.default.accept_source_route = 0` Then, apply the changes with: `sysctl --system` Disabling IPv6 Source Routing may impact network configurations that rely on this feature. Workaround: To mitigate this vulnerability on systems that do not require Wi-Fi connectivity, prevent the mac80211 kernel module from loading. 1. Blacklist the module by creating a configuration file in /etc/modprobe.d/: ``` echo "install mac80211 /bin/true" >> /etc/modprobe.d/disable-mac80211.conf ``` 2. If the module is currently loaded, unload it or restart the system: ``` modprobe -r mac80211 ``` Caveats: Disabling mac80211 disables all Wi-Fi functionality on the host. Unloading kernel modules or restarting the system will interrupt active network services and running workloads. If dependent wireless drivers are actively in use, a system reboot is required for the configuration to take effect. Workaround: To mitigate this issue, prevent module sctp from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Workaround: To mitigate this vulnerability, prevent the 'act_pedit' kernel module from loading. Create a file `/etc/modprobe.d/disable-act_pedit.conf` with the following content: `install act_pedit /bin/true` Then, regenerate the initramfs and reboot the system for the changes to take effect. This may impact network traffic control functionality that relies on the pedit action.

🔗 References (16)