UpHeron
All vulnerabilities

Servers and applications

CVE-2020-12820

Under non-default configuration, a stack-based buffer overflow in FortiOS version 6.0.10 and below, version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.

Severity
High 8.8
Published
19 Dec 2024
Last changed
17 Jun 2026
Added to UpHeron
1 Nov 2026
Fixed in
5.6.13, 6.0.11
Sources
NVD

Affected software

SoftwareAffected versions
Fortinet FortiOSServers and applications · cpe:o:fortinet:fortios
  • Every version before 5.6.13
  • From 6.0.0 before 6.0.11

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2020-12820
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2020-12820