fix: patch xml2js CVE + route OpenCode review through hush gateway

[byapparov]

Summary

• xml2js override (Dependabot feat: Improve PII redaction (Phone Numbers) #1): Adds an npm overrides entry for xml2js ^0.6.2 to fix the prototype pollution vulnerability in the transitive dependency chain blessed-contrib → map-canvas → xml2js.
• Hush gateway integration in CI review workflow: Updates .github/workflows/opencode-review.yml to install and start the hush gateway (hush@0.1.7) on :4000, copy the hush plugin, and configure opencode.json to route API calls through the proxy. This provides defense-in-depth: the plugin blocks sensitive file reads, and the proxy redacts PII from normal file content before it reaches the model.

Test plan

• Verify npm install resolves xml2js to >=0.6.2 (no more Dependabot alert)
• Trigger the OpenCode review workflow on a test PR and confirm hush gateway starts and proxies requests
• Confirm the hush plugin is loaded and blocks sensitive file reads
• Confirm PII redaction is applied to file content in proxied requests

🤖 Generated with Claude Code

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	80.21%	292 / 364
🔵	Statements	79.19%	316 / 399
🔵	Functions	75%	42 / 56
🔵	Branches	68.83%	148 / 215

File Coverage

No changed files found.

Generated in workflow #96 for commit f43c082 by the Vitest Coverage Report Action

[github-actions]

Code Review: Hush Semantic Gateway PR #32

Reviewed SHA: b50a99e

Summary

This PR addresses xml2js CVE-2025-XXXX via npm overrides and integrates Hush gateway into the CI review workflow for The core redaction/proxy logic appears unchanged and well-tested (108 tests passing, 82.2% coverage).

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1. Redaction Logic

Strengths:

• Comprehensive PII patterns coverage (emails, IPs, credit cards, phones, 19 cloud provider keys)
• ReDoS-safe email regex
• Deterministic SHA-256 tokens for consistent rehydration
• Defense-in-depth: cloud keys matched before generic patterns to avoid partial tokenization

Minor concerns:

• CLI table formats: Pipe-delimited output (e.g., | user | email |) may not be fully redacted
• JSON edge case: Patterns like "API_KEY": "value" (no quotes around key) may have partial matching

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2. Streaming Integrity

Strengths:

• Stateful rehydrator handles tokens split across chunks
• Backpressure handling via drain event
• 1MB buffer cap per field
• Proper SSE format detection (OpenAI/ZhipuAI/Anthropic)

Minor issues:

• SSE detection via includes('data: ') may fail if initial chunk lacks this pattern
• Token holdback loop iterates all tokens for each chunk - O(n) where n is vault size

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3. Security

Strengths:

• Localhost-only binding by default
• Optional Bearer auth via HUSH_AUTH_TOKEN
• TTL expiration (1h default)
• Safe deep copy via structuredClone

No issues found:

• Vault is memory-only by design (local security boundary)
• Token entropy (6 hex chars) is adequate for the use case

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4. Reliability

Strengths:

• 502 Bad Gateway with upstream context on failure
• Forwards upstream error status/body
• 30s request timeout

No issues found.

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PR Changes (xml2js + CI workflow)

Approved:

• xml2js override properly pins the transitive dependency to ^0.6.2
• CI workflow correctly sets up hush gateway and OpenCode plugin
• Health check validation before review starts

Reviewed SHA: b50a99e