ISC BIND Limiting Simultaneous TCP Clients Denial of Service Vulnerability [CVE-2018-5743]
CVE Number – CVE-2018-5743
A vulnerability in ISC BIND could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on a targeted system.The vulnerability exists because the affected software does not sufficiently limit simultaneous TCP client connections. An attacker could exploit this vulnerability by establishing simultaneous TCP connections on the targeted system. A successful exploit could cause exhaustion of all available file descriptors on the system, resulting in a DoS condition. ISC.org has confirmed the vulnerability and released software updates.
Analysis
- To exploit this vulnerability, an attacker must establish a TCP connection to the targeted system, making exploitation more difficult in environments that restrict network access from untrusted sources.
Safeguards
- 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.
Vendor Announcements
- ISC.org has released a security advisory at the following link: CVE-2018-5743: Limiting simultaneous TCP clients is ineffective
Fixed Software
- ISC.org has released software updates at the following link: bind 9.11.6-P1, bind 9.12.4-P1, bind 9.14.1
Duncan is a technology professional with over 20 years experience of working in various IT roles. He has a interest in cyber security, and has a wide range of other skills in radio, electronics and telecommunications.