CVE-2019-17659

Description

A use of hard-coded cryptographic key vulnerability in FortiSIEM version 5.2.6 may allow a remote unauthenticated attacker to obtain SSH access to the supervisor as the restricted user "tunneluser" by leveraging knowledge of the private key from another installation or a firmware image.

Remediation

Solution:

  • Please upgrade to FortiSIEM version 5.2.7 and above where this issue is resolved. Workaround (for FortiSIEM version 5.2.6 and lower): Customers who are not using the reverse tunnel feature are advised to disable SSH service on port 19999 by following the steps below : 1. SSH to the Supervisor node as the root user. 2. Remove tunneluser SSH configuration file to disable listening on port 19999: rm -f /etc/ssh/sshd_config.tunneluser echo rm -f /etc/ssh/sshd_config.tunneluser >> /etc/init.d/phProvision.sh 3. Then terminate sshd running on TCP Port 19999 as follows: pkill -f /usr/sbin/sshd -p 19999 4.Additional steps can be performed on Supervisor to remove the keys associated with tunneluser account: rm -f /opt/phoenix/deployment/id_rsa.pub.tunneluser rm -f /home/tunneluser/.ssh/authorized_keys rm -f /opt/phoenix/id_rsa.tunneluser ~admin/.ssh/id_rsa Customers are also advised to disable "tunneluser" SSH access on port 22 by following the steps bwlow: 1. SSH to the Supervisor node as the root user. 2. Add/edit the following line in sshd_config file: echo DenyUsers tunneluser >> /etc/ssh/sshd_config 3. service sshd restart

Category

3.7
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.10%
Affected: Fortinet FortiSIEM
Published at:
Updated at:

References

Link Tags
https://fortiguard.fortinet.com/psirt/FG-IR-19-296

Frequently Asked Questions

What is the severity of CVE-2019-17659?
CVE-2019-17659 has been scored as a low severity vulnerability.
How to fix CVE-2019-17659?
To fix CVE-2019-17659: Please upgrade to FortiSIEM version 5.2.7 and above where this issue is resolved. Workaround (for FortiSIEM version 5.2.6 and lower): Customers who are not using the reverse tunnel feature are advised to disable SSH service on port 19999 by following the steps below : 1. SSH to the Supervisor node as the root user. 2. Remove tunneluser SSH configuration file to disable listening on port 19999: rm -f /etc/ssh/sshd_config.tunneluser echo rm -f /etc/ssh/sshd_config.tunneluser >> /etc/init.d/phProvision.sh 3. Then terminate sshd running on TCP Port 19999 as follows: pkill -f /usr/sbin/sshd -p 19999 4.Additional steps can be performed on Supervisor to remove the keys associated with tunneluser account: rm -f /opt/phoenix/deployment/id_rsa.pub.tunneluser rm -f /home/tunneluser/.ssh/authorized_keys rm -f /opt/phoenix/id_rsa.tunneluser ~admin/.ssh/id_rsa Customers are also advised to disable "tunneluser" SSH access on port 22 by following the steps bwlow: 1. SSH to the Supervisor node as the root user. 2. Add/edit the following line in sshd_config file: echo DenyUsers tunneluser >> /etc/ssh/sshd_config 3. service sshd restart
Is CVE-2019-17659 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2019-17659 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-17659?
CVE-2019-17659 affects Fortinet FortiSIEM.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.