Brute Force Detection (BFD) is a log-based security tool that detects authentication failures and automatically bans hostile IP addresses on Linux servers.
Rather than using simple fixed failure counts, BFD uses exponential-decay pressure scoring. This helps distinguish occasional human password mistakes from sustained brute-force attacks.
This is free and open source software.
Key Features
- Log-based brute force detection for Linux servers
- Automatic IP banning
- Exponential-decay pressure scoring
- 57 service rules covering SSH, mail, FTP, web, databases, control panels, DNS, VPN, VoIP, proxies, and more
- 8 firewall backends including APF, CSF, firewalld, UFW, nftables, iptables, route, and custom commands
- IPv4 and IPv6 support
- GeoIP enrichment and optional country-based pressure weighting
- CDN and trusted proxy handling
- Repeat offender escalation
- Watch mode for low-latency detection
- Dry-run and health-check modes
- Email, Slack, Telegram, and Discord alerts
- Manual ban, unban, and active-ban listing
Website: github.com/rfxn/brute-force-detection
Support:
Developer: R-fx Networks
License: GNU General Public License v2.0
Related Software
| Intrusion Prevention for SSH | |
|---|---|
| Fail2Ban | Intrusion prevention software framework written in Python |
| SSHGuard | Protects hosts from brute-force attacks against SSH and other services |
| denyhosts | Helps thwart SSH server attacks |
| iptables | Configure the Linux 2.4.x and later packet filtering ruleset |
| CSF | ConfigServer Security & Firewall |
| reaction | Daemon that scans program outputs for repeated patterns, and takes action |
Read our verdict in the software roundup.
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