Critical severity · published Jul 24, 2020
CVE-2020-12812
Fortinet FortiOS SSL VPN Improper Authentication Vulnerability
RansomwareIn wildKEV
9.8
CVSS
45.4%
EPSS
Yes
On KEV
Description
An improper authentication vulnerability in SSL VPN in FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below may result in a user being able to log in successfully without being prompted for the second factor of authentication (FortiToken) if they changed the case of their username.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)45.4% · higher than 99% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueMay 3, 2022
Ransomware campaign useKnown
Affected products
Which versions
FO
FortiOS · Fortinet
FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below · source: vendor, NVD, KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-12812
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-12812
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://fortiguard.com/psirt/FG-IR-19-283
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