fix(expo-cicd-workflows): add URL allowlist to fetch.js to prevent SSRF#52
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xiaolai wants to merge 1 commit into
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fix(expo-cicd-workflows): add URL allowlist to fetch.js to prevent SSRF#52xiaolai wants to merge 1 commit into
xiaolai wants to merge 1 commit into
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Co-Authored-By: Claude Code <noreply@anthropic.com>
This was referenced Apr 27, 2026
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Security Fix (Medium)
plugins/expo/skills/expo-cicd-workflows/scripts/fetch.jsaccepts any URL viaprocess.argv[2]and passes it directly tofetch()without validating the scheme or domain (lines 96–107). If the script is ever invoked with attacker-controlled input outside the documented skill context, an adversary could supply an arbitrary URL — including internal metadata endpoints likehttp://169.254.169.254/— triggering a Server-Side Request Forgery (SSRF).Fix: Add a
ALLOWED_URL_PREFIXESarray containing the URLs this script legitimately needs (https://api.expo.dev/,https://raw.githubusercontent.com/expo/,https://docs.expo.dev/) and a guard functionassertAllowedUrl()that rejects any URL not matching those prefixes. The guard is called immediately after the argument is validated, before any network request is made.This is a defence-in-depth improvement. The practical risk within the skill context is low, but the fix costs nothing and makes the script's intended scope explicit.