Trim trailing dot from trusted IMDS hostnames - #652
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DNS resolvers may return hostnames with a trailing dot (e.g. `metadata.google.internal.`), which is a valid FQDN form. The previous direct equality check failed to match these, so they would not be skipped and could cause false-positive stored-SSRF blocks. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Expand normalize_hostname (sinks/socket) to also lowercase and strip
trailing dots so it is a proper canonical form for all hostname
comparisons. Use it in is_trusted_hostname instead of inline .lower()
.rstrip(".").
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Importing from sinks.socket in vulnerabilities.ssrf.imds created a cycle through sinks.socket.__init__ → aikido_zen.vulnerabilities. Move the implementation to helpers/normalize_hostname.py and have sinks/socket/normalize_hostname.py re-export from there. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
DNS resolvers sometimes return fully-qualified domain names with a trailing dot (e.g.
metadata.google.internal.). The previous direct equality check inis_trusted_hostnamedid not match this form, so GCP IMDS requests could be incorrectly flagged as stored SSRF..lower().rstrip('.')before the trusted-host lookupThis is the same fix already applied in firewall-go (PR #459 /
hostname-trailing-dot). Ported to Python, Ruby, .NET, PHP, and Java.Test plan
poetry run pytest aikido_zen/vulnerabilities/ssrf/imds_test.pypassesSummary by Aikido
🚀 New Features
⚡ Enhancements
🐛 Bugfixes
🔧 Refactors
More info