diff --git a/docs/spec/unknown_values_report.md b/docs/spec/unknown_values_report.md
index 31aff1d..7dd5963 100644
--- a/docs/spec/unknown_values_report.md
+++ b/docs/spec/unknown_values_report.md
@@ -195,28 +195,28 @@ HMAC フックからは個別に特定できなかった。
 2. `FpsMgkAppIdAuthData::getAuthData()` @ `0x000284bc` をフックして apphmac を直接キャプチャ
 3. apphmac が `HMAC(PSK, devicetoken)` かどうかをテスト (Frida で入力 216B の HMAC コールを監視)
 
-### appboot sign key (32B)
+### ~~appboot sign key (32B)~~ → **解決済み: Keychain キャッシュ**
 
 | 項目 | 値 |
 |------|-----|
 | キャプチャ値 | `38b2030dd55e3367290213ca0d16ee079524ccd24fb7221a52145fb6de016fd8` |
 | 用途 | appboot リクエスト全体 (8549B) の HMAC-SHA256 署名 |
-| **固定/可変** | **可変 (導出値)** — セッションごとに異なる可能性 |
-| **再利用可否** | **不可** — 導出元が不明なため再現できない |
-| **Python 再現** | **不可** — 導出ロジック未解明 |
-| **追加調査が必要** | ★★ apphmac と並ぶブロッカー |
+| **固定/可変** | **~~可変 (導出値)~~** → **前回セッションの Phase 2 sign key (Keychain キャッシュ)** |
+| **再利用可否** | 初回 appboot には不要 |
+| **Python 再現** | **不要** — フレッシュ appboot では sign_key_1 で署名する |
+| **追加調査** | **不要** |
 
-**既知の事実:**
-- Phase 3 KDF の出力 (sign_key_1 = `d45443fa...`) ではない
-- Phase 2 KDF の出力 (session sign key = `8887ddf1...`) でもない
-- `SHA256(sign_key_1)` でもない
-- キャッシュクリア後の再起動でも同じ値が出現 → ESN/MGK から決定的に導出されている可能性
-- Phase 2 (DH) の前に使用されている → DH 共有秘密には依存しない
+**2026-04-09 解決:**
+Netflix アプリの全データ (Library/, Documents/, tmp/) を削除してクリーンな初回起動を
+キャプチャした結果、`38b2030d` も `8887ddf1` も出現しなかった。
+これらは**前回の appboot で Phase 2 KDF から導出されたセッション鍵が iOS Keychain に
+キャッシュされていた**値に過ぎないことが確定。
 
-**調査方針:**
-1. Phase 3 KDF の中間値やバリエーションを網羅的にテスト
-2. `HMAC(sign_key_1, ESN)`, `HMAC(session_bind, ESN)` 等の候補を Python で計算し照合
-3. MslClient.framework の appboot リクエスト組立関数をデコンパイルし、署名鍵の取得パスを追跡
+フレッシュ appboot (初回起動 / キャッシュなし) では:
+1. Phase 3 KDF → sign_key_1 で appboot リクエストに署名
+2. DH 鍵交換 → Phase 2 KDF → 新セッション鍵を導出
+3. 新セッション鍵を Keychain にキャッシュ
+4. 以降のリクエストはキャッシュされたセッション鍵で署名
 
 ---
 
@@ -292,9 +292,10 @@ appboot 時の HMAC 呼び出し順序と使用鍵:
 | 値 | 固定/可変 | 再利用 | 調査優先度 | 調査内容 |
 |----|----------|--------|-----------|---------|
 | **apphmac** (32B) | 毎回可変 | 不可 | ★★ 最高 | 導出ロジック (鍵 + 入力) の解明 |
-| **appboot sign key** (32B) | 可変 (導出値) | 不可 | ★★ 最高 | 導出元の特定。Phase 3 中間値？ |
 | **devicetoken** (216B) | 可変 | 不明 | ★ 高 | 有効期限。NRM API 仕様。再利用可能期間 |
+| ~~**appboot sign key**~~ | ~~解決済み~~ | — | — | Keychain キャッシュ。初回は sign_key_1 で代替 |
 
-> **結論**: apphmac と appboot sign key の導出ロジックを解明しない限り、
-> Python 単体で appboot リクエストを構築・署名することは不可能。
-> これが現時点での最大のブロッカーである。
+> **結論**: apphmac の導出ロジックが残る唯一の最大ブロッカー。
+> appboot sign key は Keychain キャッシュと判明し、フレッシュ appboot では
+> sign_key_1 (Phase 3 KDF 出力) で署名すればよい。
+> devicetoken は有効期限が不明だが、キャプチャ値を渡すことで当面は動作する可能性がある。
diff --git a/packages/tweak/NetflixEntityAuth/.theos/_/DEBIAN/control b/packages/tweak/NetflixEntityAuth/.theos/_/DEBIAN/control
index fd4c23f..4cb0967 100644
--- a/packages/tweak/NetflixEntityAuth/.theos/_/DEBIAN/control
+++ b/packages/tweak/NetflixEntityAuth/.theos/_/DEBIAN/control
@@ -6,5 +6,5 @@ Author: tkgstrator
 Section: Tweaks
 Depends: mobilesubstrate, dev.theos.orion14 (>= 1.0.1)
 Architecture: iphoneos-arm64
-Version: 1.0.0-3+debug
-Installed-Size: 124
+Version: 1.0.0-8+debug
+Installed-Size: 140
diff --git a/packages/tweak/NetflixEntityAuth/.theos/_/var/jb/Library/MobileSubstrate/DynamicLibraries/NetflixEntityAuth.dylib b/packages/tweak/NetflixEntityAuth/.theos/_/var/jb/Library/MobileSubstrate/DynamicLibraries/NetflixEntityAuth.dylib
index d1ffc41..d91d111 100755
Binary files a/packages/tweak/NetflixEntityAuth/.theos/_/var/jb/Library/MobileSubstrate/DynamicLibraries/NetflixEntityAuth.dylib and b/packages/tweak/NetflixEntityAuth/.theos/_/var/jb/Library/MobileSubstrate/DynamicLibraries/NetflixEntityAuth.dylib differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/last_package b/packages/tweak/NetflixEntityAuth/.theos/last_package
index 9883594..8220f2e 100644
--- a/packages/tweak/NetflixEntityAuth/.theos/last_package
+++ b/packages/tweak/NetflixEntityAuth/.theos/last_package
@@ -1 +1 @@
-./packages/work.tkgstrator.netflixentityauth_1.0.0-3+debug_iphoneos-arm64.deb
+./packages/work.tkgstrator.netflixentityauth_1.0.0-8+debug_iphoneos-arm64.deb
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/NetflixEntityAuth.dylib b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/NetflixEntityAuth.dylib
index d1ffc41..d91d111 100755
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/NetflixEntityAuth.dylib and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/NetflixEntityAuth.dylib differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib
index db80b20..912f74a 100755
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib.dSYM/Contents/Resources/DWARF/NetflixEntityAuth.dylib b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib.dSYM/Contents/Resources/DWARF/NetflixEntityAuth.dylib
index dc0ee70..244f3bb 100644
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib.dSYM/Contents/Resources/DWARF/NetflixEntityAuth.dylib and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.dylib.dSYM/Contents/Resources/DWARF/NetflixEntityAuth.dylib differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.swiftsourceinfo b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.swiftsourceinfo
index faafa89..9c16fd4 100644
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.swiftsourceinfo and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/NetflixEntityAuth.swiftsourceinfo differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/Sources/NetflixEntityAuthC/Tweak.m.276b477d.o b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/Sources/NetflixEntityAuthC/Tweak.m.276b477d.o
index a99c8cd..16b3c0b 100644
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diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift.276b477d.swiftdeps b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift.276b477d.swiftdeps
index 7da256c..6e8f661 100644
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift.276b477d.swiftdeps and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift.276b477d.swiftdeps differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.priors b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.priors
index 5ebe707..9669b12 100644
Binary files a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.priors and b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.priors differ
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.swiftdeps b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.swiftdeps
index 57f76e8..e37340c 100644
--- a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.swiftdeps
+++ b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/master.276b477d.swiftdeps
@@ -1,7 +1,7 @@
 version: "Swift version 5.8 (swift-5.8-RELEASE)"
 options: "46ac4fc8a6fab716165f87c6eadba55bec7c9ab0850730661a3e566653e8c94c"
-build_start_time: [1775726738, 664805000]
-build_end_time: [1775726738, 850699000]
+build_start_time: [1775727995, 699198000]
+build_end_time: [1775727995, 829239000]
 inputs:
-  "/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift": [1775726738, 0]
+  "/home/vscode/app/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/generated/NetflixEntityAuth.xc.swift": [1775727995, 0]
   "Sources/NetflixEntityAuth/Tweak.x.swift": [1775724899, 0]
diff --git a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/output-file-map.276b477d.json b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/output-file-map.276b477d.json
index 1ef8ee0..3d60695 100644
--- a/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/output-file-map.276b477d.json
+++ b/packages/tweak/NetflixEntityAuth/.theos/obj/debug/arm64/output-file-map.276b477d.json
@@ -1 +1 @@
-{"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift":{"swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.swiftdeps","object":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.o","dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.Td"},"Sources\/NetflixEntityAuth\/Tweak.x.swift":{"dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.Td","swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.swiftdeps","object":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.o"},"":{"swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/master.276b477d.swiftdeps","dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/master.276b477d.Td"}}
+{"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift":{"dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.Td","swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.swiftdeps","object":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/generated\/NetflixEntityAuth.xc.swift.276b477d.o"},"":{"dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/master.276b477d.Td","swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/master.276b477d.swiftdeps"},"Sources\/NetflixEntityAuth\/Tweak.x.swift":{"dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.Td","swift-dependencies":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.swiftdeps","object":"\/home\/vscode\/app\/packages\/tweak\/NetflixEntityAuth\/.theos\/obj\/debug\/arm64\/Sources\/NetflixEntityAuth\/Tweak.x.swift.276b477d.o"}}
diff --git a/packages/tweak/NetflixEntityAuth/.theos/packages/work.tkgstrator.netflixentityauth-1.0.0 b/packages/tweak/NetflixEntityAuth/.theos/packages/work.tkgstrator.netflixentityauth-1.0.0
index e440e5c..301160a 100644
--- a/packages/tweak/NetflixEntityAuth/.theos/packages/work.tkgstrator.netflixentityauth-1.0.0
+++ b/packages/tweak/NetflixEntityAuth/.theos/packages/work.tkgstrator.netflixentityauth-1.0.0
@@ -1 +1 @@
-3
\ No newline at end of file
+8
\ No newline at end of file