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Known Exploited Vulnerability
9.8
CRITICAL CVSS 3.1
CVE-2020-12812
Fortinet FortiOS SSL VPN Improper Authentication Vulnerability - [Actively Exploited]
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.

INFO

Published Date :

July 24, 2020, 11:15 p.m.

Last Modified :

Oct. 24, 2025, 12:53 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

Description :

Fortinet FortiOS SSL VPN contains an improper authentication vulnerability that may allow a user to login successfully without being prompted for the second factor of authentication (FortiToken) if they change the case in their username.

Required Action :

Apply updates per vendor instructions.

Notes :

https://nvd.nist.gov/vuln/detail/CVE-2020-12812

Affected Products

The following products are affected by CVE-2020-12812 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Fortinet fortios
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 HIGH [email protected]
CVSS 3.1 CRITICAL [email protected]
CVSS 3.1 CRITICAL 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Upgrade FortiOS to address an improper authentication vulnerability.
  • Upgrade to FortiOS version 6.0.10, 6.2.4, 6.4.1 or later.
  • Apply the workaround from the advisory, if upgrading is not possible.
Public PoC/Exploit Available at Github

CVE-2020-12812 has a 5 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2020-12812.

URL Resource
https://fortiguard.com/psirt/FG-IR-19-283 Vendor Advisory
https://fortiguard.com/psirt/FG-IR-19-283 Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-12812 US Government Resource
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2020-12812 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2020-12812 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
soosmile/POC

None

Updated: 9 months, 2 weeks ago
9 stars 1 fork 1 watcher
Born at : June 21, 2022, 7:45 a.m. This repo has been linked 944 different CVEs too.
Profile Photo
triw0lf/Security-Matters-22

Resources for Security Matters talk 2022

Updated: 3 years, 8 months ago
1 stars 0 fork 0 watcher
Born at : April 20, 2022, 5:31 p.m. This repo has been linked 39 different CVEs too.
Profile Photo
Ostorlab/KEV

Ostorlab KEV: One-command to detect most remotely known exploitable vulnerabilities. Sourced from CISA KEV, Google's Tsunami, Ostorlab's Asteroid and Bug Bounty programs.

cisa-kev vulnerability 0day cisa exploits

Updated: 3 months, 1 week ago
588 stars 42 fork 42 watcher
Born at : April 19, 2022, 8:58 a.m. This repo has been linked 1290 different CVEs too.
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r0eXpeR/supplier

主流供应商的一些攻击性漏洞汇总

Updated: 5 months, 4 weeks ago
808 stars 143 fork 143 watcher
Born at : Nov. 8, 2021, 2:12 a.m. This repo has been linked 93 different CVEs too.
Profile Photo
irinarenteria/attackerkb-clj

AttackerKB API Clojure client.

Clojure

Updated: 4 years, 9 months ago
0 stars 0 fork 0 watcher
Born at : April 14, 2021, 7:22 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2020-12812 vulnerability anywhere in the article.

  • europa.eu
Cyber Brief 26-01 - December 2025

Cyber Brief (December 2025)January 5, 2025 - Version: 1TLP:CLEARExecutive summaryWe analysed 368 open source reports for this Cyber Security Brief[^1].Relating to cyber policy and law enforcement, the ... Read more

Published Date: Jan 05, 2026 (1 week, 5 days ago)
  • security.nl
Nog altijd ruim 10.000 Fortinet-firewalls kwetsbaar voor vijf jaar oud lek

The Shadowserver Foundation neemt voortaan een ernstige kwetsbaarheid in Fortinet SSL-VPN (CVE-2020-12812) op in haar dagelijkse Vulnerable HTTP Report. Hoewel dit lek inmiddels vijf jaar bekend is en ... Read more

Published Date: Jan 05, 2026 (1 week, 6 days ago)
  • BleepingComputer
Over 10K Fortinet firewalls exposed to actively exploited 2FA bypass

Over 10,000 Fortinet firewalls are still exposed online and vulnerable to ongoing attacks exploiting a five-year-old critical two-factor authentication (2FA) bypass vulnerability. Fortinet released Fo ... Read more

Published Date: Jan 02, 2026 (2 weeks, 1 day ago)
  • CybersecurityNews
10,000+ Fortinet Firewalls Still Exposed to 5-year Old MFA Bypass Vulnerability

Over 10,000 Fortinet firewalls worldwide remain vulnerable to CVE-2020-12812, a multi-factor authentication (MFA) bypass flaw disclosed over five and a half years ago. Shadowserver recently added the ... Read more

Published Date: Jan 02, 2026 (2 weeks, 1 day ago)
  • The Hacker News
⚡ Weekly Recap: MongoDB Attacks, Wallet Breaches, Android Spyware, Insider Crime & More

Dec 29, 2026Ravie LakshmananHacking News / Cybersecurity Last week's cyber news in 2025 was not about one big incident. It was about many small cracks opening at the same time. Tools people trust ev ... Read more

Published Date: Dec 29, 2025 (2 weeks, 5 days ago)
  • security.nl
Fortinet waarschuwt voor misbruik van vijf jaar oud VPN-lek in FortiOS

Aanvallers maken actief misbruik van een vijf jaar oude kwetsbaarheid in het SSL VPN-onderdeel van FortiOS, zo waarschuwt Fortinet. FortiOS is het besturingssysteem van Fortinet dat op allerlei netwer ... Read more

Published Date: Dec 29, 2025 (2 weeks, 5 days ago)
  • BleepingComputer
Fortinet warns of 5-year-old FortiOS 2FA bypass still exploited in attacks

Fortinet has warned customers that threat actors are still actively exploiting a critical FortiOS vulnerability that allows them to bypass two-factor authentication (2FA) when targeting vulnerable For ... Read more

Published Date: Dec 29, 2025 (2 weeks, 5 days ago)
  • The Hacker News
Fortinet Warns of Active Exploitation of FortiOS SSL VPN 2FA Bypass Vulnerability

Dec 25, 2025Ravie LakshmananVulnerability / Enterprise Security Fortinet on Wednesday said it observed "recent abuse" of a five-year-old security flaw in FortiOS SSL VPN in the wild under certain co ... Read more

Published Date: Dec 25, 2025 (3 weeks, 3 days ago)
  • CybersecurityNews
Hackers Exploiting Three-Year-Old FortiGate Vulnerability to Bypass 2FA on Firewalls

Cybercriminals are actively abusing a long-patched Fortinet FortiGate flaw from July 2020, slipping past two-factor authentication (2FA) on firewalls and potentially granting unauthorized access to VP ... Read more

Published Date: Dec 25, 2025 (3 weeks, 3 days ago)
  • Daily CyberSecurity
Hackers Revive 2020 FortiGate Flaw to Bypass 2FA

Fortinet has issued a warning regarding the active exploitation of a three-year-old vulnerability that allows attackers to bypass two-factor authentication (2FA) on FortiGate firewalls simply by chang ... Read more

Published Date: Dec 25, 2025 (3 weeks, 3 days ago)
  • CybersecurityNews
Ransomware Attack 2025 Recap – From Critical Data Extortion to Operational Disruption

The ransomware landscape in 2025 has reached new heights, evolving from a cybersecurity issue into a strategic threat to national security and global economic stability. This year saw a 34%-50% surge ... Read more

Published Date: Dec 19, 2025 (4 weeks, 1 day ago)
  • The Register
Play ransomware crims exploit SimpleHelp flaw in double-extortion schemes

Groups linked with the Play ransomware have exploited more than 900 organizations, the FBI said Wednesday, and have developed a number of new techniques in their double-extortion campaigns - including ... Read more

Published Date: Jun 04, 2025 (7 months, 1 week ago)
  • Cybersecurity News
Unmasking Play Ransomware: Tactics, Techniques, and Mitigation Strategies

EDR detection of threat actor attack actions used in the Lateral Movement phase | Source: AhnLabPlay ransomware, also known as Balloonfly or PlayCrypt, has emerged as a significant cyber threat since ... Read more

Published Date: Jan 10, 2025 (1 year ago)

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2020-12812 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Modified Analysis by [email protected]

    Oct. 24, 2025

    Action Type Old Value New Value
    Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-12812 Types: US Government Resource
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 22, 2025

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-12812
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 21, 2025

    Action Type Old Value New Value
    Removed Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-12812
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 21, 2025

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-12812
  • Modified Analysis by [email protected]

    Feb. 24, 2025

    Action Type Old Value New Value
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Feb. 04, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-287
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://fortiguard.com/psirt/FG-IR-19-283
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Reanalysis by [email protected]

    Feb. 13, 2024

    Action Type Old Value New Value
    Added CWE NIST CWE-287
  • CWE Remap by [email protected]

    Jul. 12, 2022

    Action Type Old Value New Value
    Changed CWE CWE-287 CWE-178
  • Initial Analysis by [email protected]

    Jul. 28, 2020

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://fortiguard.com/psirt/FG-IR-19-283 No Types Assigned https://fortiguard.com/psirt/FG-IR-19-283 Vendor Advisory
    Added CWE NIST CWE-287
    Added CPE Configuration OR *cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:* versions up to (excluding) 6.0.10 *cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:* versions from (including) 6.2.0 up to (excluding) 6.2.4 *cpe:2.3:o:fortinet:fortios:6.4.0:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 7.5
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

45.02 }} -0.98%

score

0.97477

percentile