🛡️ Sentinel: [HIGH] 보안 향상 - CSP 'unsafe-inline' 제거 및 nonce 적용

[seonghobae]

🛡️ Sentinel: [HIGH] 보안 향상 - CSP 'unsafe-inline' 제거 및 nonce 적용

🚨 Severity: HIGH
💡 Vulnerability: 정적으로 생성되는 HTML 파일의 Content Security Policy(CSP)에 unsafe-inline이 허용되어 있어, CSS 인젝션(CSS Injection) 공격에 대한 방어가 취약했습니다.
🎯 Impact: 악의적인 디렉토리/파일 이름 등을 통해 인라인 스타일이 주입될 경우 제한된 형태의 XSS 공격이 가능해질 수 있습니다.
🔧 Fix:

1. 인라인 style="..." 속성을 제거하고 .item-link, .empty-msg와 같은 CSS 클래스로 대체했습니다.
2. 매번 고유한 암호학적 난수(UUID 기반 nonce)를 생성하여 <style> 태그와 CSP 메타 태그에 추가함으로써 허용된 스타일만 렌더링되도록 수정했습니다 (style-src 'nonce-...';).
   ✅ Verification: ./gradlew test를 실행하여 테스트가 성공적으로 통과함을 확인했으며, 100% 테스트 커버리지를 유지합니다. 생성된 index.html 파일에 인라인 스타일이 없으며 nonce가 올바르게 작동함을 검증했습니다.

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PR created automatically by Jules for task 10642124570899679186 started by @seonghobae

[google-labs-jules]

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[seonghobae]

Closing as superseded during org-wide PR triage. Keeping #111 as the canonical PR for the same overlapping topic: CSP unsafe-inline/nonce hardening. This PR is stale/conflicted or has review blockers, so retaining one current PR reduces duplicated review and merge conflict work.

[google-labs-jules]

Closing as superseded during org-wide PR triage. Keeping #111 as the canonical PR for the same overlapping topic: CSP unsafe-inline/nonce hardening. This PR is stale/conflicted or has review blockers, so retaining one current PR reduces duplicated review and merge conflict work.

Understood. Acknowledging that this work is now obsolete and stopping work on this task.