AlmaLinux OS 9 must disable mounting of udf.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-269348 | ALMA-09-030380 | SV-269348r1050230_rule | CCI-000381 | medium |
| Description | ||||
| Removing support for unneeded filesystem types reduces the local attack surface of the server. The UDF filesystem is used to write DVDs and so could assist in data exfiltration, the so-called "sneakernet". Note that Microsoft Azure uses UDF. | ||||
| STIG | Date | |||
| Cloud Linux AlmaLinux OS 9 Security Technical Implementation Guide | 2026-02-27 | |||
Related Frameworks
3 paths across 3 frameworks
Related Frameworks
NIST 800-531 mapping
CM-7
1.00
- DISA · V1R6 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1711 mapping
3.4.6
1.00
- DISA · V1R6 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
- NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-000381
1.00
- DISA · V1R6 · disa_xccdf · related
Details
Check Text (C-269348r1050230_chk)
Verify that AlmaLinux OS 9 disables the ability to load the udf kernel module with the following command:
$ grep udf /etc/modprobe.conf /etc/modprobe.d/*
blacklist udf
If the command does not return any output, or the line is commented out, and use of UDF is not documented with the information system security officer (ISSO) as an operational requirement, this is a finding.
Fix Text (F-73280r1048421_fix)
To configure the system to prevent the udf kernel module from being loaded, create a *.conf file in /etc/modprobe.d/ with the following content:
install udf /bin/false
blacklist udf