By ThreatListPro Security Team · Published February 27, 2026 · Last verified: February 28, 2026
VPN brute force attacks have exploded since 2024. Automated botnets scan the internet for GlobalProtect, SSL-VPN, AnyConnect, and other VPN portals, then launch sustained credential attacks that lock out legitimate users, overwhelm helpdesks, and create real security risk. Choosing the right protection depends on your budget, timeline, and technical resources.
We evaluated the five most common approaches to VPN brute force protection, ranking each by effectiveness, cost, setup time, and ongoing maintenance requirements.
Summary Comparison
| Solution | Cost | Setup Time | Effectiveness | Maintenance |
|---|---|---|---|---|
| ThreatListPro | $9.99/mo | 5 minutes | High (VPN-specific) | None |
| Enterprise Threat Feeds | $500+/mo | Weeks | High (broad coverage) | Moderate |
| AbuseIPDB + Scripting | Free-$199/mo | Hours-days | Moderate (not VPN-specific) | High |
| Geo-Blocking | Free | 30 minutes | Low-Moderate (false positives) | Low-Moderate |
| Manual IP Blocking | Free | Ongoing | Low (reactive only) | Very High |
1. ThreatListPro Recommended
$9.99/month | 5-minute setup | Zero maintenance
ThreatListPro is a curated IP blocklist specifically designed for VPN brute force protection. Every IP on the list was captured by honeypots running real VPN portal software (GlobalProtect, SSL-VPN, AnyConnect). You paste a single EDL URL into your firewall configuration, create a deny rule, and commit. The list updates weekly with new attacker IPs, and old entries are automatically removed.
- Pros: Fastest deployment of any solution. VPN-specific data means near-zero false positives. Works with every major firewall (Palo Alto, FortiGate, pfSense, OPNsense, SonicWall, Cisco, Sophos). No scripts, no servers, no cron jobs.
- Cons: Covers VPN brute force only, not other attack types. Requires a firewall that supports EDLs (most enterprise firewalls do).
- Best for: IT teams that need immediate relief from VPN brute force attacks. MSPs managing multiple client firewalls. Organizations without dedicated security staff.
2. Enterprise Threat Feeds
$500+/month | Weeks to deploy | Moderate maintenance
Enterprise threat intelligence platforms like CrowdStrike Falcon Intelligence, Recorded Future, and Mandiant Advantage provide comprehensive IP threat data covering all attack types. These feeds include VPN brute force IPs among millions of other threat indicators.
- Pros: Comprehensive coverage across all threat types. Backed by large research teams. Rich context (threat actor attribution, campaign tracking, confidence scoring).
- Cons: Expensive ($500-5,000+/month). Not specifically curated for VPN brute force. Requires integration work to feed data into your firewall. Typically needs a SOC team to manage alerts and tune rules.
- Best for: Large enterprises with dedicated security operations teams and budgets for comprehensive threat intelligence.
3. AbuseIPDB + Custom Scripting
Free (limited) or $19-199/month API | Hours-days to set up | High maintenance
AbuseIPDB is a community-driven IP reputation database. By querying their API, you can extract IPs with high confidence scores and build a custom blocklist for your firewall. This requires writing a script, hosting the output, and scheduling regular updates.
- Pros: Free tier available. Large community database. API provides confidence scores for filtering. Useful as an investigation tool alongside blocking.
- Cons: Not a blocklist service; requires custom development. Community-reported data includes false positives. Not curated for VPN-specific threats. API rate limits restrict how many IPs you can query. Ongoing script maintenance as their API evolves.
- Best for: Organizations with developer resources who want to build a custom solution and are comfortable maintaining it long-term.
4. Geo-Blocking
Free (built into firewalls) | 30 minutes to configure | Low-moderate maintenance
Geo-blocking restricts VPN access to traffic from selected countries. If all your users are in one country, blocking all other countries eliminates the majority of foreign attack traffic. It is a blunt instrument but effective for reducing volume.
- Pros: Free and built into most firewalls. Easy to configure. Reduces attack volume by 60-80%.
- Cons: High false positive rate (blocks traveling employees, remote workers, business partners). Does not stop attacks from allowed countries, including domestic cloud infrastructure. Requires manual updates when business needs change.
- Best for: Small, domestic-only organizations with no international travel or remote workers. Useful as a first layer combined with other solutions.
5. Manual IP Blocking
Free | No setup (ongoing effort) | Very high maintenance
The most basic approach: review firewall logs, identify attacker IPs, and manually add them to a deny list. This is reactive by definition, as you can only block IPs after they have already attacked you.
- Pros: No cost. No external dependencies. Full control over what gets blocked.
- Cons: Does not scale. By the time you block an IP, the damage (lockouts, log noise) has already occurred. Attackers rotate IPs constantly, making manual blocking a never-ending treadmill. Consumes significant admin time.
- Best for: Extremely small environments with minimal attack traffic, or as a temporary measure while deploying a proper solution.
Frequently Asked Questions
What is the fastest way to stop VPN brute force attacks?
A curated IP blocklist configured as an External Dynamic List (EDL) on your firewall. ThreatListPro can be deployed in under 5 minutes. You paste a single URL into your firewall configuration, create a deny rule, and commit. Known attacker IPs are blocked at the network perimeter before they reach your VPN portal.
Is a paid blocklist worth it when free options exist?
Free options have significant limitations. AbuseIPDB requires custom scripting. Geo-blocking causes false positives. Manual blocking is unsustainable. A paid service like ThreatListPro at $9.99/month provides a curated, VPN-specific, EDL-ready blocklist with zero maintenance. The hidden labor cost of free alternatives typically exceeds $9.99/month within the first week.
Should I use multiple VPN protection solutions together?
Yes. Defense in depth is recommended. Combine geo-blocking (free, reduces bulk traffic), ThreatListPro (blocks specific attacker IPs from all countries), rate limiting (slows unknown attackers), and MFA (prevents credential compromise). Each layer addresses gaps that others miss.
Do enterprise threat feeds like CrowdStrike cover VPN brute force?
Enterprise platforms include IP threat data but are not specifically focused on VPN brute force. Their feeds cover all threat types, require integration work, and cost $500+/month. For the specific problem of VPN brute force protection, a focused solution like ThreatListPro is more effective and far less expensive.