Hackers Exploited Fortinet Vulnerabilities to Gain Access of a U.S. Municipal Government Webserver


Just recently, APT group or the state-sponsored hackers have actually exploited the vulnerabilities in an unpatched Fortinet VPN to compromise the webserver of a U.S. municipal government web server, as reported by the FBI (Federal Bureau of Examination).

The APT (Advanced Persistent Threat) hackers developed brand-new servers, domain controllers, and workstation user accounts simply after gaining access to the webserver of the city government organization.

While after revealing the matter, the FBI asserted that, “The FBI is continuing to warn about Advanced Persistent Threat (APT) actors exploiting Fortinet vulnerabilities. As of a minimum of May 2021, an APT star group likely exploited a Fortigate device to access a webserver hosting the domain for a U.S. municipal government.”

According to the FBI, the APT hackers are building WADGUtilityAccount and elie accounts on the hacked systems of the city government body, to use them to build up and exfiltrate data from the compromised network of the victims.

FBI and CISA already warned

APT actors mainly targeted the Fortinet appliances.

The vulnerabilities that are actively exploited by the APT group are pointed out listed below:-.

Earlier, the FBI and the Cybersecurity and Infrastructure Security Agency (CISA) have actually currently alerted in April about the attacks that are performed by the APT hackers by exploiting several exploits in Fortinet FortiOS servers.

Here, to work out the vulnerable U.S. election support systems the danger stars have primarily and continually made use of the Fortinet SSL VPN vulnerability (CVE-2018-13379).

To block these compromise attempts that are carried out by the APT hackers, the FBI and CISA have shared some mitigations, and here they are pointed out below:-.

Immediately patch the CVEs 2018-13379, 2020-12812, and 2019-5591.
Inspect all the domain controllers, servers, workstations, and active directories.
Re-check the Task Scheduler for unacknowledged arranged tasks.
Regularly revise the antivirus logs.
Regularly back up information.
Implement network segmentation.
Install most current patches and updates.
Use multifactor authentication.
Avoid reusing old passwords, and try to change passwords regularly.
Disable unused remote access/Remote Desktop Protocol (RDP) ports.
Audit user accounts with administrative advantages.
Install and regularly upgrade antivirus tools.
Constantly utilize a virtual private network (VPN).
Disable hyperlinks in received e-mails.


The APT group has actually used the following tools to execute these attacks:-.

Even in November 2020 hackers abused the CVE-2018-13379 to exfiltrate the VPN qualifications of more than 50,000 Fortinet VPN servers that consist of vital infrastructures like banks and governments.

Mimikatz (credential theft).
MinerGate (crypto mining).
WinPEAS (privilege escalation).
SharpWMI (Windows Management Instrumentation).
BitLocker activation when not anticipated (information file encryption).
WinRAR where not expected (archiving).
FileZilla where not expected (file transfer).

According to the reports, over the years the unpatched Fortinet servers were mostly targeted by state-sponsored hackers or APT hackers..

Also Read: Hackers Exploit FortiOS Vulnerabilities to Access Government and Technology Services Networks.


Apart from this, the professionals have actually described that APT hackers may utilize the jeopardized servers to target critical facilities sectors for the execution of future attacks.

To avoid such attacks and improve the compromised systems and networks the FBI and the CISA have strongly recommended the victims to follow the above-mentioned mitigation measures provided by them.

To acquire access to important infrastructure networks the APT hackers have actually used numerous typical attack vectors like spearphishing.

Tools utilized.