SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

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…

HIGH 8.8EPSS 0.86%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.86%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.86% probability · 57th percentile
CISA KEV
Not listed
Weakness
CWE-121, CWE-787
Affected
fortinet/fortios
Source
psirt@fortinet.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.