Attack Surface Scan vs crt.sh: Side-by-Side Comparison (2026)

Attack Surface Scan: Agentless external attack surface monitoring with continuous change detection. built by Attack Surface Scan. Core capabilities include Agentless external attack surface scanning with no installation required, Continuous scheduled re-scanning with change detection and diff tracking, HTTP security header analysis (HSTS, CSP, CORS, cookie flags)..

crt.sh: Bash script for subdomain enumeration via crt.sh certificate transparency logs. Core capabilities include Subdomain enumeration via certificate transparency logs, Automated querying of crt.sh website, Parsing and filtering of crt.sh output..

Both serve the External Attack Surface Management market but differ in approach, feature depth, and target audience.

Attack Surface Scan differentiates with Agentless external attack surface scanning with no installation required, Continuous scheduled re-scanning with change detection and diff tracking, HTTP security header analysis (HSTS, CSP, CORS, cookie flags). crt.sh differentiates with Subdomain enumeration via certificate transparency logs, Automated querying of crt.sh website, Parsing and filtering of crt.sh output.

Attack Surface Scan integrates with Slack, Claude, Claude Code, ChatGPT, Codex and 4 more. crt.sh integrates with crt.sh. Check integration compatibility with your existing security stack before deciding.

Attack Surface Scan and crt.sh serve similar External Attack Surface Management use cases: both are External Attack Surface Management tools, both cover Subdomain Enumeration, SSL, DNS Security. Key differences: Attack Surface Scan is Commercial while crt.sh is Free. Review the feature comparison above to determine which fits your requirements.