Red Hat Security Advisory: kernel security update
🔗 CVE IDs covered (4)
📋 Description
CVE-2026-17523 — kernel: can:bcm: arbitrary kernel code execution leading to escalate privileges CVE-2026-53006 — kernel: ipv6: fix possible UAF in icmpv6_rcv() CVE-2026-64002 — kernel: ipv4: free net->ipv4.sysctl_local_reserved_ports after unregister_net_sysctl_table() CVE-2026-74581 — kernel: net: ipv6: use-after-free in fib6_rule_suppress due to stale res->rt6 pointer
🎯 Affected products74
- Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- bpftool-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- bpftool-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- bpftool-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- bpftool-debuginfo-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- bpftool-debuginfo-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- bpftool-debuginfo-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-0:4.18.0-477.163.1.el8_8.src as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-0:4.18.0-477.163.1.el8_8.src as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-abi-stablelists-0:4.18.0-477.163.1.el8_8.noarch as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-abi-stablelists-0:4.18.0-477.163.1.el8_8.noarch as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-core-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-core-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-core-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-debug-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-debug-core-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-core-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-core-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-debug-debuginfo-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-debuginfo-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-debuginfo-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- kernel-debug-devel-0:4.18.0-477.163.1.el8_8.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-devel-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v.8.8)
- kernel-debug-devel-0:4.18.0-477.163.1.el8_8.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v.8.8)
- +44 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. 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. Workaround: To mitigate this vulnerability, prevent the `bcm` kernel module from loading if it is not required. Create a file named `/etc/modprobe.d/blacklist-bcm.conf` with the content `blacklist bcm`. A system reboot is required for this change to take effect. This mitigation may impact functionality that relies on the CAN BCM module. Workaround: To mitigate this issue, disable the `ipv6` kernel module at boot using the kernel command-line parameter: ``` grubby --update-kernel=ALL --args="ipv6.disable=1" ``` A reboot is required for this change to take effect. To verify after reboot: ``` cat /proc/cmdline | grep -o ipv6.disable=1 sysctl net.ipv6.conf.all.disable_ipv6 ``` Applications or services that rely on the IPv6 protocol cannot use this mitigation and should prioritize applying the fix.
🔗 References (7)
- selfhttps://access.redhat.com/errata/RHSA-2026:61932
- externalhttps://access.redhat.com/security/updates/classification/#important
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2492363
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2502363
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2507407
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2520980
- selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_61932.json