CVE Vulnerabilities

CVE-2018-1111

Improper Neutralization of Special Elements used in a Command ('Command Injection')

Published: May 17, 2018 | Modified: Feb 12, 2023
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.9 HIGH
AV:A/AC:M/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
7.5 CRITICAL
CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Ubuntu

DHCP packages in Red Hat Enterprise Linux 6 and 7, Fedora 28, and earlier are vulnerable to a command injection flaw in the NetworkManager integration script included in the DHCP client. A malicious DHCP server, or an attacker on the local network able to spoof DHCP responses, could use this flaw to execute arbitrary commands with root privileges on systems using NetworkManager and configured to obtain network configuration using the DHCP protocol.

Weakness

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

Affected Software

Name Vendor Start Version End Version
Fedora Fedoraproject 26 (including) 26 (including)
Fedora Fedoraproject 27 (including) 27 (including)
Fedora Fedoraproject 28 (including) 28 (including)
Red Hat Enterprise Linux 6 RedHat dhcp-12:4.1.1-53.P1.el6_9.4 *
Red Hat Enterprise Linux 6.4 Advanced Update Support RedHat dhcp-12:4.1.1-34.P1.el6_4.2 *
Red Hat Enterprise Linux 6.5 Advanced Update Support RedHat dhcp-12:4.1.1-38.P1.el6_5.1 *
Red Hat Enterprise Linux 6.6 Advanced Update Support RedHat dhcp-12:4.1.1-43.P1.el6_6.2 *
Red Hat Enterprise Linux 6.6 Telco Extended Update Support RedHat dhcp-12:4.1.1-43.P1.el6_6.2 *
Red Hat Enterprise Linux 6.7 Extended Update Support RedHat dhcp-12:4.1.1-49.P1.el6_7.1 *
Red Hat Enterprise Linux 7 RedHat dhcp-12:4.2.5-68.el7_5.1 *
Red Hat Enterprise Linux 7.2 Advanced Update Support RedHat dhcp-12:4.2.5-42.el7_2.1 *
Red Hat Enterprise Linux 7.2 Telco Extended Update Support RedHat dhcp-12:4.2.5-42.el7_2.1 *
Red Hat Enterprise Linux 7.2 Update Services for SAP Solutions RedHat dhcp-12:4.2.5-42.el7_2.1 *
Red Hat Enterprise Linux 7.3 Extended Update Support RedHat dhcp-12:4.2.5-47.el7_3.1 *
Red Hat Enterprise Linux 7.4 Extended Update Support RedHat dhcp-12:4.2.5-58.el7_4.4 *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 RedHat imgbased-0:1.0.16-0.1.el7ev *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 RedHat ovirt-node-ng-0:4.2.0-0.20170814.0.el7 *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 RedHat redhat-release-virtualization-host-0:4.2-3.0.el7 *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 RedHat redhat-virtualization-host-0:4.2-20180508.0 *
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 RedHat rhvm-appliance-0:4.2-20180504.0 *

Extended Description

Command injection vulnerabilities typically occur when:

Many protocols and products have their own custom command language. While OS or shell command strings are frequently discovered and targeted, developers may not realize that these other command languages might also be vulnerable to attacks. Command injection is a common problem with wrapper programs.

Potential Mitigations

  • Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

References