Malware & Threats

FortiBleed: 86,000 Fortinet Device Credentials Compromised

The large-scale credential theft campaign hit roughly half of the internet-accessible Fortinet firewalls and VPNs.

Fortinet zero-day

CISA is urging organizations to harden their internet-accessible Fortinet devices in response to a large-scale credential theft campaign that likely impacts over 86,000 firewalls and VPNs.

Referred to as FortiBleed, the campaign was flagged earlier this week. SOCRadar initially warned of over 30,000 compromised Fortinet devices potentially exposing enterprise networks to hacking, and has since updated that figure to 86,000.

“Discovered in June 2026, the operation has produced a verified database of over 86,644 confirmed working credentials across 194 countries, all collected from internet-facing Fortinet infrastructure,” the company says.

The hackers have compiled a database of usernames and passwords, tested using automated scripts. Some credentials were likely compromised in previous incidents, but never rotated.

Security researcher Kevin Beaumont, together with Hudson Rock, worked with some of the impacted organizations and verified that the logins are valid and fairly recent.

“The data comprises roughly 50% of all Fortinet firewall devices facing the internet, based on polling from Shodan,” Beaumont says.

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According to security researcher Bob Diachenko, the campaign has been orchestrated by a Russian-speaking threat actor and at least four organizations have been fully compromised.

“They intercept SSL VPN authentication, crack hashes on a 45-GPU cluster managed via Hashtopolis, and pivot into internal Active Directory environments,” Diachenko says.

The attackers are estimated to have executed roughly 1.16 billion credential attempts targeting more than 320,000 FortiGate targets, as well as 2.1 billion brute-force attempts against over 160,000 MSSQL servers.

According to Hudson Rock, the campaign has hit thousands of organizations, “including major government entities and critical infrastructure providers”.

Cybersecurity firm Huntress too has confirmed the broad reach of the campaign: “While the overall campaign is massive, Huntress has cross-referenced the listed IP addresses against their own data corpus and identified 845 partner organizations specifically impacted by this credential dump.”

On Thursday, CISA issued an alert on FortiBleed, urging Fortinet customers to take hardening actions: terminate active sessions and reset credentials, ensure they use Password-Based Key Derivation Function 2 (PBKDF2) algorithm to store admin logins, review logs to identify suspicious activity, enable phishing-resistant MFA, and lock down management access to reduce the attack surface.

Related: Chinese Cybercrime Group in Spotlight for Record Campaign Pace

Related: Over 500 Organizations Hit in Years-Long Phishing Campaign

Related: Palo Alto Zero-Day Exploited in Campaign Bearing Hallmarks of Chinese State Hacking

Related: Microsoft Warns of Sophisticated Phishing Campaign Targeting US Organizations

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