CVE-2023-39189: Fedoraproject Fedora

Medium severity, CVSS 6.0. EPSS: 0.4% chance of exploitation in the next 30 days.

A flaw was found in the Netfilter subsystem in the Linux kernel. The nfnl_osf_add_callback function did not validate the user mode controlled opt_num field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, leading to a crash or information disclosure.

Affected products

• Fedoraproject Fedora: version 38 only
• Linux Linux Kernel: before 6.6 (fixed in 6.6)
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only

Published 2023-10-09. Last modified 2026-06-17.