K45435121 : DNS Express vulnerability CVE-2018-5538

Security Advisory Description

On F5 BIG-IP DNS 13.1.0-13.1.0.7, 12.1.3-12.1.3.5, DNS Express / DNS Zones accept NOTIFY messages on the management interface from source IP addresses not listed in the ‘Allow NOTIFY From’ configuration parameter when the db variable “dnsexpress.notifyport” is set to any value other than the default of “0”. (CVE-2018-5538)

Impact

This vulnerability may allow a malicious actor to cause DNS Express to constantly check for updates. An update only occurs if the zone’s serial number has changed.