A vulnerability in the NetworkManager component of Red Hat Enterprise Linux (RHEL) could allow an unauthenticated, remote attacker to inject and execute arbitrary script commands on a targeted system.
The vulnerability exists in the dhclient package scripts /etc/NetworkManager/dispatcher.d/11-dhclient on RHEL 7 and /etc/NetworkManager/dispatcher.d/10-dhclient on RHEL 6. An attacker with access to the local network or a malicious DHCP server could exploit the vulnerability by spoofing DHCP responses to the system. A successful exploit could allow the attacker to inject and execute arbitrary script commands with root privileges on the system.
Red Hat has confirmed the vulnerability and released software updates.
To exploit this vulnerability, an attacker must have access to the local network or control of a malicious DHCP server on the local network in order to send responses to the targeted system. These access requirements may reduce the likelihood of a successful exploit.
It is important to note that the vulnerability only exists in the Red Hat NetworkManager dhclient integration scripts and does not impact the upstream Internet Systems Consortium (ISC) DHCP source code.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators are advised to run both firewall and antivirus applications to minimize the potential of inbound and outbound threats.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators can help protect affected systems from external attacks by using a solid firewall strategy.
Administrators are advised to monitor affected systems.
Red Hat has released updated software for registered subscribers at the following link: Red Hat Network. Red Hat packages can be updated on Red Hat Enterprise Linux versions 5 and later using the yum tool.
6 (IA-32, PPC, PPC 64, s390, s390x, x86_64, i386) | 7 (x86_64, ppc, ppc64, s390, s390x, SRPMS, ppc64le, aarch64, noarch) | 4 Year Extended Update Support 7.4 (Base, x86_64) | 4 Year Extended Update Support 7.3 (Base, x86_64) | 4 Year Extended Update Support 7.2 (Base, x86_64)
Red Hat Enterprise Linux Server TUS
6.6 (x86_64) | 7.2 (x86_64)
Red Hat Virtualization ELS
7 (Base, x86_64)
Red Hat Virtualization
4 (Base, x86_64)
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Cisco Multivendor Vulnerability Alerts respond to vulnerabilities identified in third-party vendors' products. These alerts contain information compiled from diverse sources and provide comprehensive technical descriptions, objective analytical assessments, workarounds and practical safeguards, and links to vendor advisories and patches.