Don't follow HTTP redirects off the scan target - #24
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Header, stack, service, and web fetchers used urllib's default redirect following. A public target that 302s to metadata or RFC1918 made the agent connect there (scanner SSRF). Return the 3xx instead, matching LLM/SIEM/vuln_prober/takeover hardening. Co-authored-by: dmitryflynn <dmitryflynn@users.noreply.github.com>
This was referenced Aug 29, 2026
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Bug and impact
Target-facing HTTP fetchers (header audit, stack fingerprint, service probe, web fingerprint, HTTP auth enum) used
urllib.request.urlopen, which follows 3xx by default — including cross-host hops.Trigger: Scan an authorized public host with headers/stack/probe/full enabled. The host returns
302 Location: http://169.254.169.254/latest/meta-data/(or RFC1918). The agent connects to that destination. On a cloud VM this can pull IMDS into scan evidence (_body_snippet, fingerprints, "open" web-root findings).LLM URLs, SIEM, vuln_prober, takeover, and active validation already refuse redirects. These auditors did not.
Root cause
Incomplete hardening:
urlopenfollows redirects unless a customHTTPRedirectHandlerraises. The remaining fetchers never installed one.Fix
Shared
src/http_fetch.urlopen_no_redirectsurfaces 3xx asHTTPErrorand never fetches the Location. Existing HTTPError handlers already return that status/headers, so 302s are audited in place instead of chasing metadata.Validation
python3 -m pytest test_http_ssrf_redirect.py— 7 passed (local origin 302s to a second server; destination hit count stays 0; normal 200 still fetched).Related suites (
test_header_audit,test_probers,test_web_fingerprint,test_stack_fingerprint,test_service_enum,test_active_validation,test_security_hardening,test_takeover) — 220 passed.