Inside FortiBleed: Reverse Engineering the CyberStrike Harvester Behind a Global FortiGate Credential Factory

Arctic Wolf Labs reverse-engineered the CyberStrike Harvester v1.5 binary (a Go-based Linux ELF) used in the FortiBleed campaign — a large-scale credential compromise operation targeting internet-facing Fortinet FortiGate firewalls across 194 countries. The campaign operates as a closed-loop credential pipeline: credential stuffing and password spraying gain initial access, FortiGate configurations and traffic captures are exported, the CyberStrike Harvester parses pcap/pcapng/FortiGate text to extract NetNTLM, Kerberos, cookies, and cleartext credentials, a Telegram-bot-orchestrated Hashcat/Hashtopolis GPU cluster cracks hashes, and Impacket-based tools then perform AD enumeration, SMB validation, and DFS file-share exfiltration (one logged run collected 121 GB). The operators prioritize targets by revenue and geography. Attribution remains low-confidence Russian-speaking based on tool branding, an operator handle, and Russian-language UI strings. Remediation requires immediate session termination, credential rotation, MFA enforcement, and specific FortiOS password-policy steps to eliminate legacy SHA-256 hashes from configuration exports.

Source: https://arcticwolf.com/resources/blog/inside-fortibleed-reverse-engineering-the-cyberstrike-harvester-behind-a-global-fortigate-credential-factory. 8 Sync News only summarizes and links out; content copyright belongs to the authors and original sources.