Zero-Day Advisory

Fortinet Discovers MikroTik RouterOS Denial of Service Vulnerability


Fortinet's FortiGuard Labs has discovered a Denial of Service vulnerability in MikroTik's RouterOS.

RouterOS is an operating system based on the Linux kernel, which implements functionalities normally used by Internet Service Providers (ISPs). RouterOS, supported by MikroTik and its user community, provides a wide variety of configuration examples. RouterOS is embedded in MikroTik's RouterBOARD product line, focused on small- and medium-sized internet access providers that typically provide broadband access in remote areas.

A Denial of Service exists in the MikroTik's RouterOS before 6.46. Successful exploitation of this vulnerability would allow a remote attacker to restart the system via a crafted UPnP XML payload.


Users should apply patch provided by MikroTik


Fortinet reported the vulnerability to MikroTik on August 21, 2019.

MikroTik confirmed the vulnerability on August 23, 2019 and stated this vulnerability only affects to RouterOS before 6.46. Later versions are no longer using libexpat.

MikroTik released the patch for this vulnerability within 6.45.5 stable release on 28 August, 2019.


This vulnerability was discovered by Tin Duong of Fortinet's FortiGuard Labs

IPS Subscription

Fortinet customers who subscribe to Fortinet's intrusion prevention (IPS) service should be protected against this vulnerability with the appropriate configuration parameters in place. Fortinet's IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by FortiGuard Labs, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.