CrowdSec vs scanlogd

CrowdSec is an open-source security stack designed to detect and block malicious IP addresses to protect infrastructure and applications. Its Security Engine analyzes logs and requests for harmful behavior, while the Remediation Component blocks IPs identified by that engine across supported platforms. CrowdSec says analysis takes place locally and logs do not leave the user's infrastructure. Its AppSec Component can provide web application firewall protection. The free Community offering includes real-time decision management, audit support, AWS CloudTrail scenarios, CAPI allow lists, and Kubernetes audit acquisition. IP Reputation data includes contextual criteria, activity timelines, autonomous system and IP range reputation, MITRE technique classification, and hourly updates. Listed integrations include Microsoft Sentinel, AWS log sources, WordPress, Cloudflare, Docker, and Kubernetes. The Community Security Engine is free. The IP Reputation API is listed at $49 a month for 5,000 queries; other listed services include blocklists and threat-intelligence options. CrowdSec lists Linux, macOS, and Windows among its platforms, with API, extension, self-hosted, and web options.

scanlogd is a free TCP port scan detection tool for Linux and self-hosted deployments. It captures packets through Linux raw sockets, libnids, or libpcap. The project advises against using libpcap alone when fragmented IP packets matter, recommending libnids for non-Linux systems or monitoring an entire network. The official download page lists release 2.2.8, release files and signatures, an Openwall archive, and source browsing through GitHub. scanlogd is listed in Owl, Debian GNU/Linux, Gentoo Linux, ALT Linux, and OpenWrt, with ports in OpenBSD and FreeBSD collections. A contributed precompiled Win32 build is also linked. The project describes scanlogd as designed to be totally safe to use and points readers to its manual page and a Phrack article. Openwall offers commercial configuration, compilation, and installation support at US $250/hour with a six-hour minimum or US $9,000/week; fixed-price quotes are available for sufficiently specific projects.