RHSA-2023:4789HighCVSS 8.8

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

Published
August 29, 2023
Last Modified
August 10, 2026

🔗 CVE IDs covered (13)

CVE-2021-33656 →CVE-2022-50318 →CVE-2022-50615 →CVE-2023-1829 →CVE-2023-2124 →CVE-2023-3390 →CVE-2023-20593 →CVE-2023-35788 →CVE-2022-42896 →CVE-2023-1637 →CVE-2023-2002 →CVE-2023-28466 →CVE-2023-44466 →

📋 Description

CVE-2021-33656 — kernel: when setting font with malicious data by ioctl PIO_FONT, kernel will write memory out of bounds CVE-2022-42896 — kernel: use-after-free in l2cap_connect and l2cap_le_connect_req in net/bluetooth/l2cap_core.c CVE-2022-50318 — kernel: perf/x86/intel/uncore: Fix reference count leak in hswep_has_limit_sbox() CVE-2022-50615 — kernel: perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map() CVE-2023-1637 — kernel: save/restore speculative MSRs during S3 suspend/resume CVE-2023-1829 — kernel: Use-after-free vulnerability in the Linux Kernel traffic control index filter CVE-2023-2002 — Kernel: bluetooth: Unauthorized management command execution CVE-2023-2124 — kernel: OOB access in the Linux kernel's XFS subsystem CVE-2023-3390 — kernel: UAF in nftables when nft_set_lookup_global triggered after handling named and anonymous sets in batch requests CVE-2023-20593 — hw: amd: Cross-Process Information Leak CVE-2023-28466 — kernel: tls: race condition in do_tls_getsockopt may lead to use-after-free or NULL pointer dereference CVE-2023-35788 — kernel: cls_flower: out-of-bounds write in fl_set_geneve_opt() CVE-2023-44466 — kernel: buffer overflow in ceph file net/ceph/messenger_v2.c

🎯 Affected products132

  • Red Hat CodeReady Linux Builder EUS (v.8.6)
  • Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • Red Hat Virtualization 4 Hypervisor for RHEL 8
  • bpftool-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-0:4.18.0-372.70.1.el8_6.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat CodeReady Linux Builder EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat CodeReady Linux Builder EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat CodeReady Linux Builder EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • bpftool-debuginfo-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Virtualization 4 Hypervisor for RHEL 8
  • kernel-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-0:4.18.0-372.70.1.el8_6.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-0:4.18.0-372.70.1.el8_6.src as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-abi-stablelists-0:4.18.0-372.70.1.el8_6.noarch as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-core-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-core-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-core-0:4.18.0-372.70.1.el8_6.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-core-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-debug-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-debug-0:4.18.0-372.70.1.el8_6.ppc64le as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-debug-0:4.18.0-372.70.1.el8_6.s390x as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-debug-0:4.18.0-372.70.1.el8_6.x86_64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • kernel-debug-core-0:4.18.0-372.70.1.el8_6.aarch64 as a component of Red Hat Enterprise Linux BaseOS EUS (v.8.6)
  • +102 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: 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: This flaw can be mitigated by disabling Bluetooth on the operating system level. The kernel modules can be prevented from being loaded by using system-wide modprobe rules. For instructions on how to disable Bluetooth on RHEL please refer to https://access.redhat.com/solutions/2682931. Alternatively Bluetooth can be disabled within the hardware or at BIOS level which will also provide an effective mitigation as the kernel will not be able to detect that Bluetooth hardware is present on the system. Workaround: To mitigate this issue, prevent the module cls_tcindex from being loaded. Please see https://access.redhat.com/solutions/41278 on 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 don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Workaround: This flaw can be mitigated by preventing the affected Transport Layer Security (TLS) kernel module from loading during the boot time. Ensure the module is added into the blacklist file. ~~~ Refer: How do I blacklist a kernel module to prevent it from loading automatically? https://access.redhat.com/solutions/41278 ~~~ Workaround: This flaw can be mitigated by preventing the affected `cls_flower` kernel module from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278.

🔗 References (13)