High severity · published Dec 19, 2024
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…
8.8
CVSS
0.9%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
FortiOS · Fortinet
6.0.0 through 6.0.10; 5.6.0 through 5.6.12 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-12820
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-12820
Vendor Advisory
https://fortiguard.fortinet.com/psirt/FG-IR-20-083
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