ALMA-09-040720 - AlmaLinux OS 9 must disable access to network bpf system call from nonprivileged processes.

Information

Loading and accessing the packet filters programs and maps using the bpf() system call has the potential of revealing sensitive information about the kernel state.

Solution

Configure AlmaLinux OS 9 to prevent privilege escalation through the kernel by disabling access to the bpf syscall with the following command:

$ echo "kernel.unprivileged_bpf_disabled = 1" > /etc/sysctl.d/60-bpf.conf

Load settings from all system configuration files with the following command:

$ sysctl --system

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_CL_AlmaLinux_OS_9_V1R1_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-2, CAT|II, CCI|CCI-001082, Rule-ID|SV-269422r1050305_rule, STIG-ID|ALMA-09-040720, Vuln-ID|V-269422

Plugin: Unix

Control ID: 8bc520cc9f8d5014e076987e93f836d3c270892b20a4ac5dd751fe50b2f20bda