CISA KEV · Known exploitedCritical

CVE-2020-12812

Fortinet FortiOS

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
9.8
EPSS
49.3%
98.8% percentile
CISA KEV
Listed
Published
2020.07.25
PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV
Exploit probability49.3%
Technical severityCVSS 9.8

Vulnerability overview

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.

Affected product and versions

Product
Fortinet FortiOS
Affected versions
FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below, < 6.0.10, >= 6.2.0 < 6.2.4, 6.4.0
Fixed versions
6.0.10, 6.2.4

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
CISA required action

Apply updates per vendor instructions.

Due date: 2022.05.03
  1. 1
    Identify

    Confirm that Fortinet FortiOS and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-178, CWE-287
KEV added
2021.11.03
Ransomware use
확인됨
CVE-2020-12812 — Fortinet FortiOS | SECUFOCUS NOW