Fortinet FortiOS CVE-2019-15703 Insufficient Entropy Vulnerability



Date Discovered

October 18, 2019


Fortinet FortiOS is prone to an insufficent entropy vulnerability. Remote attackers can exploit this issue to perform side-channel attacks and obtain sensitive information. This aids in other attacks.

Technologies Affected

  • Fortinet FortiOS 2.36.0
  • Fortinet FortiOS 2.50.0
  • Fortinet FortiOS 2.50.0 MR5
  • Fortinet FortiOS 2.8.0 MR10
  • Fortinet FortiOS 2.80 MR12
  • Fortinet FortiOS 2.80.0
  • Fortinet FortiOS 3.0 MR1
  • Fortinet FortiOS 3.0 MR2
  • Fortinet FortiOS 3.0.0
  • Fortinet FortiOS 4.3.10
  • Fortinet FortiOS 4.3.12
  • Fortinet FortiOS 4.3.13
  • Fortinet FortiOS 4.3.14
  • Fortinet FortiOS 4.3.8
  • Fortinet FortiOS 4.3.8 B0537
  • Fortinet FortiOS 4.3.8 B0630
  • Fortinet FortiOS 5.0
  • Fortinet FortiOS 5.0.1
  • Fortinet FortiOS 5.0.2
  • Fortinet FortiOS 5.0.3
  • Fortinet FortiOS 5.0.5
  • Fortinet Fortios 4.1.10
  • Fortinet Fortios 4.1.11
  • Fortinet Fortios 4.2.12
  • Fortinet Fortios 4.2.13
  • Fortinet Fortios 4.3.0
  • Fortinet Fortios 4.3.15
  • Fortinet Fortios 4.3.16
  • Fortinet Fortios 4.3.17
  • Fortinet Fortios 4.3.18
  • Fortinet Fortios 4.3.19
  • Fortinet Fortios 4.3.9
  • Fortinet Fortios 5.0.0
  • Fortinet Fortios 5.0.4
  • Fortinet Fortios 5.0.6
  • Fortinet Fortios 5.0.7
  • Fortinet Fortios 5.0.7
  • Fortinet Fortios 5.0.8
  • Fortinet Fortios 5.0.9


Block external access at the network boundary, unless external parties require service.
If global access isn't needed, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of successful exploits.

Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, run all applications with the minimal amount of privileges required for functionality.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This includes but is not limited to requests that include suspicious URI sequences.

Communicate sensitive information over encrypted channels.
Ensure that only encrypted channels are used for communicating sensitive information.

Updates are available. Please see the references or vendor advisory for more information.



Shaanan Cohney of the University of Pennsylvania

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