diff --git a/.jules/sentinel.md b/.jules/sentinel.md
index 499037d..74c4075 100644
--- a/.jules/sentinel.md
+++ b/.jules/sentinel.md
@@ -10,3 +10,7 @@
 **Vulnerability:** Unhandled exceptions when accessing `localStorage` in strict browser privacy modes (e.g., when cookies are blocked).
 **Learning:** Browsers throw a `SecurityError` when `localStorage` is accessed and the user has blocked third-party cookies or is in a strict privacy mode. If unhandled, this crashes the executing script, leading to a degraded user experience (DoS-like behavior for privacy-conscious users).
 **Prevention:** Always wrap `localStorage.getItem` and `localStorage.setItem` in `try-catch` blocks to fail securely and fall back to sensible defaults.
+## 2026-06-23 - Prevent Reverse Tabnabbing via noopener noreferrer
+**Vulnerability:** External links were missing `rel="noopener noreferrer"` (and missing `target="_blank"`), which exposes the site to reverse tabnabbing attacks where the newly opened page can access `window.opener` and navigate the original page to a malicious URL.
+**Learning:** The static homepage had several external links without protection against this vulnerability.
+**Prevention:** Always include `target="_blank" rel="noopener noreferrer"` for external links to prevent reverse tabnabbing and protect user sessions.
diff --git a/index.html b/index.html
index dbb0157..f6371cb 100644
--- a/index.html
+++ b/index.html
@@ -40,7 +40,7 @@
         <a href="#projects" data-i18n="nav.projects">프로젝트</a>
         <a href="#forks" data-i18n="nav.forks">Fork</a>
         <a href="#work" data-i18n="nav.work">작업</a>
-        <a href="https://github.com/ContextualWisdomLab">GitHub</a>
+        <a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab">GitHub</a>
       </nav>
       <div class="language-switch" role="group" aria-label="Language">
         <button type="button" data-lang="ko" aria-pressed="true">KO</button>
@@ -57,7 +57,7 @@ <h1 data-i18n="hero.title">맥락지혜 연구실</h1>
             구슬이 서 말이어도 꿰어야 보배이듯, 문서, 메일, 로그, 회의록을 맥락 안에서 엮어 사람이 무엇을 결정하고 무엇을 실행할지 보이게 하는 AI 의사결정 지원 시스템을 연구하고 만듭니다.
           </p>
           <div class="hero-actions" role="group" aria-label="Homepage actions">
-            <a class="button primary" href="https://github.com/ContextualWisdomLab" data-i18n="hero.primaryCta">GitHub 보기</a>
+            <a target="_blank" rel="noopener noreferrer" class="button primary" href="https://github.com/ContextualWisdomLab" data-i18n="hero.primaryCta">GitHub 보기</a>
             <a class="button secondary" href="#dikw" data-i18n="hero.secondaryCta">DIKW 보기</a>
           </div>
         </div>
@@ -251,19 +251,19 @@ <h2 data-i18n="references.title">참고문헌</h2>
         <ol class="reference-list">
           <li>
             <span data-i18n="references.ackoff">Ackoff, R. L. (1989). From data to wisdom. Journal of Applied Systems Analysis, 16(1), 3-9.</span>
-            <a href="https://faculty.ung.edu/kmelton/documents/datawisdom.pdf">https://faculty.ung.edu/kmelton/documents/datawisdom.pdf</a>
+            <a target="_blank" rel="noopener noreferrer" href="https://faculty.ung.edu/kmelton/documents/datawisdom.pdf">https://faculty.ung.edu/kmelton/documents/datawisdom.pdf</a>
           </li>
           <li>
             <span data-i18n="references.baskarada">Baskarada, S., &amp; Koronios, A. (2013). Data, information, knowledge, wisdom (DIKW): A semiotic theoretical and empirical exploration of the hierarchy and its quality dimension. Australasian Journal of Information Systems, 18(1).</span>
-            <a href="https://doi.org/10.3127/ajis.v18i1.748">https://doi.org/10.3127/ajis.v18i1.748</a>
+            <a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.3127/ajis.v18i1.748">https://doi.org/10.3127/ajis.v18i1.748</a>
           </li>
           <li>
             <span data-i18n="references.fricke">Frické, M. (2009). The knowledge pyramid: A critique of the DIKW hierarchy. Journal of Information Science, 35(2), 131-142.</span>
-            <a href="https://doi.org/10.1177/0165551508094050">https://doi.org/10.1177/0165551508094050</a>
+            <a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1177/0165551508094050">https://doi.org/10.1177/0165551508094050</a>
           </li>
           <li>
             <span data-i18n="references.brienza">Brienza, J. P., Kung, F. Y. H., Santos, H. C., Bobocel, D. R., &amp; Grossmann, I. (2018). Wisdom, bias, and balance: Toward a process-sensitive measurement of wisdom-related cognition. Journal of Personality and Social Psychology, 115(6), 1093-1126.</span>
-            <a href="https://doi.org/10.1037/pspp0000171">https://doi.org/10.1037/pspp0000171</a>
+            <a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1037/pspp0000171">https://doi.org/10.1037/pspp0000171</a>
           </li>
         </ol>
       </section>
@@ -324,31 +324,31 @@ <h2 data-i18n="projects.title">공개 프로젝트</h2>
         </div>
         <div class="naruon-grid project-grid">
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/naruon" data-i18n="projects.naruonTitle">Naruon</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/naruon" data-i18n="projects.naruonTitle">Naruon</a></h3>
             <p data-i18n="projects.naruonBody">메일, 첨부, 일정, 작업을 맥락으로 묶어 판단과 실행으로 연결하는 AI 이메일 워크스페이스입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/pg-erd-cloud" data-i18n="projects.pgErdTitle">pg-erd-cloud</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/pg-erd-cloud" data-i18n="projects.pgErdTitle">pg-erd-cloud</a></h3>
             <p data-i18n="projects.pgErdBody">PostgreSQL 스키마를 리버스 엔지니어링하고 ERD와 DDL 공유 흐름으로 관리하는 클라우드 MVP입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/bandscope" data-i18n="projects.bandscopeTitle">BandScope</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/bandscope" data-i18n="projects.bandscopeTitle">BandScope</a></h3>
             <p data-i18n="projects.bandscopeBody">곡을 섹션, 역할, 템포, 연습 우선순위로 분석하는 로컬 우선 리허설 앱입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/codec-carver" data-i18n="projects.codecCarverTitle">codec-carver</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/codec-carver" data-i18n="projects.codecCarverTitle">codec-carver</a></h3>
             <p data-i18n="projects.codecCarverBody">긴 녹음을 메타데이터를 보존한 FLAC/Opus 조각으로 변환하는 Python CLI입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/newsdom-api" data-i18n="projects.newsdomTitle">newsdom-api</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/newsdom-api" data-i18n="projects.newsdomTitle">newsdom-api</a></h3>
             <p data-i18n="projects.newsdomBody">스캔된 일본어 신문 PDF를 기사, 제목, 본문, 이미지 구조의 DOM형 JSON으로 파싱하는 API입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/scopeweave" data-i18n="projects.scopeweaveTitle">scopeweave</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/scopeweave" data-i18n="projects.scopeweaveTitle">scopeweave</a></h3>
             <p data-i18n="projects.scopeweaveBody">트리 편집, 진행률 계산, CSV/JSON, 주간 Gantt를 지원하는 정적 HTML/CSS/JS WBS 플래너입니다.</p>
           </article>
           <article>
-            <h3><a href="https://github.com/ContextualWisdomLab/VibeSec" data-i18n="projects.vibesecTitle">VibeSec</a></h3>
+            <h3><a target="_blank" rel="noopener noreferrer" href="https://github.com/ContextualWisdomLab/VibeSec" data-i18n="projects.vibesecTitle">VibeSec</a></h3>
             <p data-i18n="projects.vibesecBody">바이브코딩 앱을 위한 보안 가드레일입니다. AI 개발 도구 규칙, 정적 점검, 리뷰와 수정 프롬프트를 다룹니다.</p>
           </article>
         </div>
@@ -419,7 +419,7 @@ <h2 data-i18n="work.title">연구에서 제품으로</h2>
       >
       <p>
         <span data-i18n="footer.founded">Founded by</span>
-        <a href="https://github.com/seonghobae">Seongho Bae</a>.
+        <a target="_blank" rel="noopener noreferrer" href="https://github.com/seonghobae">Seongho Bae</a>.
         <span data-i18n="footer.line">Context into judgment. Judgment into action.</span>
       </p>
     </footer>