Red Hat Security Advisory: kernel security and bug fix update
🔗 CVE IDs covered (4)
📋 Description
CVE-2023-0461 — kernel: net/ulp: use-after-free in listening ULP sockets CVE-2023-1281 — kernel: tcindex: use-after-free vulnerability in traffic control index filter allows privilege escalation CVE-2023-1390 — kernel: remote DoS in TIPC kernel module CVE-2023-32233 — kernel: netfilter: use-after-free in nf_tables when processing batch requests can lead to privilege escalation
🎯 Affected products100
- Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- bpftool-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- bpftool-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- bpftool-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- bpftool-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- bpftool-debuginfo-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- bpftool-debuginfo-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- bpftool-debuginfo-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- bpftool-debuginfo-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.src as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.src as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.src as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-abi-whitelists-0:4.18.0-193.109.1.el8_2.noarch as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- kernel-abi-whitelists-0:4.18.0-193.109.1.el8_2.noarch as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-abi-whitelists-0:4.18.0-193.109.1.el8_2.noarch as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-core-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-core-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- kernel-core-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-core-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-debug-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-debug-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS AUS (v. 8.2)
- kernel-debug-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- kernel-debug-0:4.18.0-193.109.1.el8_2.x86_64 as a component of Red Hat Enterprise Linux BaseOS TUS (v. 8.2)
- kernel-debug-core-0:4.18.0-193.109.1.el8_2.ppc64le as a component of Red Hat Enterprise Linux BaseOS E4S (v. 8.2)
- +70 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, prevent module tls 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: This flaw can be mitigated by preventing the affected traffic control index filter (cls_tcindex) 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: 1. This flaw can be mitigated by preventing the affected netfilter (nf_tables) kernel module from being loaded. For instructions on how to blacklist a kernel module, please see https://access.redhat.com/solutions/41278. 2. If the module cannot be disabled, on non-containerized deployments of Red Hat Enterprise Linux, the mitigation is to disable user namespaces: ``` # echo "user.max_user_namespaces=0" > /etc/sysctl.d/userns.conf # sysctl -p /etc/sysctl.d/userns.conf ``` On containerized deployments, such as Red Hat OpenShift Container Platform, do not use the second mitigation (disabling user namespaces) as the functionality is needed to be enabled. The first mitigation (blacklisting nf_tables) is still viable for containerized deployments, providing the environment is not using netfilter.
🔗 References (7)
- selfhttps://access.redhat.com/errata/RHSA-2023:4125
- externalhttps://access.redhat.com/security/updates/classification/#important
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2176192
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2178212
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2181847
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2196105
- selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2023/rhsa-2023_4125.json