Harden CONNECT header handling against injection and spoofing - #24
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Reject CR/LF/NUL in outbound proxy CONNECT headers and copy only X-ProxyMesh-* CONNECT response headers onto origin responses without overwriting existing origin values. Co-authored-by: ProxyMesh AI <proxymeshai@users.noreply.github.com>
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September 1, 2026 17:22
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Left a non-blocking comment and assigned a reviewer. This is not a Dependabot version bump, so it is outside the auto-approval policy and needs human review. Cursor Bugbot and Cursor Security Agent checks were not present.
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Drop the ProxyMesh-only allowlist. Copy any CONNECT response header that is not hop-by-hop or security-sensitive, and never overwrite origin values. Pin GitHub Actions to commit SHAs. Co-authored-by: ProxyMesh AI <proxymeshai@users.noreply.github.com>
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Sep 1, 2026
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Reject CR/LF/NUL in outbound proxy CONNECT headers, and stop copying arbitrary CONNECT response headers onto origin HTTPS responses.
Outbound:
proxy_headersnames and values are validated before they are written into CONNECT (urllib3/requests/cloudscraper/autoscraper and pycurl). httpx and aiohttp already rejected control characters.Inbound: Only
X-ProxyMesh-*CONNECT headers are merged intoresponse.headers, and they never overwrite an origin header. Sensitive headers such asSet-Cookie,Location, andContent-Typeare not copied. The full CONNECT set is available onresponse.proxy_headers.Adds
test_header_security.pyand a CI unit-test job that does not needPROXY_URL.