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TI-2020-10182 Aliases CVE-2020-12812GHSA-r9cj-q2hj-hfq9

Improper authentication in Fortinet FortiOS

Priority CRITICAL 99Exploited in the wildCWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-287.

Summary

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.

Why it matters now

Exploitation Active In CISA KEV since 2021-11-03CISA due date 2022-05-03Known ransomware use
EPSS 0.45379 98th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Active
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—Fortinet FortiOSFortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below—No fix listedCNA
  • Fortinet FortiOS Vendor— Affected FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*before 6.0.10; 6.2.0 to before 6.2.4VulnerableFortinet
cpe:2.3:o:fortinet:fortios:6.4.0:*:*:*:*:*:*:*6.4.0VulnerableFortinet
  • cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:* Versions before 6.0.10; 6.2.0 to before 6.2.4 Vulnerable ·Fortinet
  • cpe:2.3:o:fortinet:fortios:6.4.0:*:*:*:*:*:*:* Versions 6.4.0 Vulnerable ·Fortinet

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2021-11-03 Added to CISA KEV
  2. 2026-10-02 Threatist record created from CVE-2020-12812
  3. 2026-10-03 Alias added: GHSA-r9cj-q2hj-hfq9

References

Advisory 1

  • TI-2026-20057 Authentication bypass in Fortinet FortiWeb KEVCVSS 3.1CRITICAL 9.4
  • TI-2025-18911 Heap-based buffer overflow in Fortinet FortiSwitchManager KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-36904 Authentication bypass in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-15234 A use of externally-controlled format string in Fortinet FortiOS versions 7.4.0 through… KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-14448 Out-of-bounds write in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-12585 Heap-based buffer overflow in Fortinet FortiOS-6K7K KEVCVSS 3.1CRITICAL 9.8
See all 276 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences