RHEL 8 Kernel Updates Fix eBPF Privilege Escalation and Use-After-Free Flaws

Red Hat released Important security updates for Red Hat Enterprise Linux 8 kernel and Real Time kernel deployments, remediating multiple vulnerabilities including CVE-2023-2163, an eBPF verifier-pruning flaw that can permit arbitrary kernel-memory reads and writes, privilege escalation, and container escape. Other fixes address a use-after-free in NVMe-over-TCP crypto cleanup (CVE-2023-5178), an AMD cross-process information disclosure issue (CVE-2023-20593), a DVB Common Interface driver use-after-free (CVE-2022-45919), network scheduler defects, and an SCTP NULL-pointer dereference.

Affected organizations should deploy the applicable RHEL 8 kernel packages, including kernel-rt-4.18.0-513.9.1.rt7.311.el8_9 for covered Real Time offerings and kernel-4.18.0-372.80.1.el8_6 for RHEL 8.6 extended-support systems, then reboot to activate the fixes. Red Hat also delivered a kpatch update for RHEL 8.2 SAP Solutions that mitigates CVE-2023-3812, an oversized-packet flaw in the TUN driver; its live-patch module loads automatically and does not require a conventional reboot. Red Hat notes that exploiting CVE-2023-2163 on RHEL generally requires CAP_SYS_ADMIN or root because unprivileged eBPF is disabled by default.