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cis-ubuntu1204-v110-6-17

DevOps & Security
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Ensure Biosdevname is not enabled

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_12.04_LTS_Server_Benchmark_v1.1.0/cis-ubuntu1204-v110-6-17/SKILL.md

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6.17 Ensure Biosdevname is not enabled (Scored)

Profile Applicability

  • Level 1

Description

biosdevname is an external tool that works with the udev framework for naming devices.

biosdevname uses three methods to determine NIC names:

  1. PCI firmware spec 3.1
  2. smbios (matches # after "em" to OEM # printed on board or housing)
  3. PCI IRQ Routing Table (uses # of NIC position in the device history). If the BIOS does not support biosdevname, no NICs are re-named.

Rationale

biosdevname is an external tool that works with the udev framework for custom renaming of system hardware connections made by the kernel and BIOS. As allowing the renaming of devices can severely disrupt network communications by creating resource conflicts and provide an attack vector for denial of service exploits, this capability should be disabled or restricted according to the needs of the organization.

Audit Procedure

Using Command Line

Run the following command:

dpkg -s biosdevname

Expected Result

Ensure package status is not-installed or dpkg returns no info is available.

Remediation

Using Command Line

Uninstall the biosdevname package:

apt-get purge biosdevname

Default Value

Not installed by default on Ubuntu 12.04 LTS Server.

References

  • CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

Profile

Level 1 - Scored