diff --git a/.github/workflows/bandit.yml b/.github/workflows/bandit.yml
index 6db7276da..6c6d4900a 100644
--- a/.github/workflows/bandit.yml
+++ b/.github/workflows/bandit.yml
@@ -24,6 +24,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
       - uses: astral-sh/setup-uv@11f9893b081a58869d3b5fccaea48c9e9e46f990 # v8.3.2
         with:
           version: "0.8.6"
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 84ace55d4..1c356b122 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -29,6 +29,8 @@ jobs:
       contents: read
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.22.3
diff --git a/.github/workflows/security-audit.yml b/.github/workflows/security-audit.yml
index 7d880c1a1..90ce48fd3 100644
--- a/.github/workflows/security-audit.yml
+++ b/.github/workflows/security-audit.yml
@@ -24,6 +24,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+        with:
+          persist-credentials: false
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.22.3
diff --git a/CHANGELOG.md b/CHANGELOG.md
index eea696893..70a6d785a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@
 - Display the analyzed song tempo (BPM) as a badge in the rehearsal workspace.
 - 각 합주 역할(Role)별 개인 연습 진행도를 0~100% 범위로 기록 및 시각화할 수 있는 연습 진척도(`practiceProgress`) 트래커 기능 추가. UI 컨트롤(슬라이더 및 +/- 버튼)과 한/영 다국어 지원 포함.
 
+### Fixed
+
+- Disable persisted GitHub checkout credentials before dependency lifecycle execution in the `security-audit`, `release`, and `bandit` workflows.
+
 ## [0.1.3] - 2026-04-29
 
 ### Fixed
diff --git a/docs/security/dependency-policy.md b/docs/security/dependency-policy.md
index f7271e68d..11a1b7f7f 100644
--- a/docs/security/dependency-policy.md
+++ b/docs/security/dependency-policy.md
@@ -44,6 +44,7 @@ Because of that, dependency review, security audit, SBOM generation, and supply-
 - dependency graph or dependency submission coverage must stay enabled wherever GitHub supports it for the repository state
 - GitHub dependency review must gate PRs into `develop` and `main`
 - GitHub Actions workflows that affect the supply chain must stay SHA pinned and least-privilege
+- dependency-install and audit jobs must disable persisted checkout credentials before untrusted dependency lifecycle code can execute
 - third-party actions require source-trust review, maintenance review, permission review, and commit-SHA pinning before admission
 
 ## New dependency admission rule
diff --git a/services/analysis-engine/tests/test_security_audit_workflow_credentials.py b/services/analysis-engine/tests/test_security_audit_workflow_credentials.py
new file mode 100644
index 000000000..5a15b31f3
--- /dev/null
+++ b/services/analysis-engine/tests/test_security_audit_workflow_credentials.py
@@ -0,0 +1,42 @@
+"""Dependency-workflow checkout credential-boundary regression tests."""
+
+from pathlib import Path
+
+REPOSITORY_ROOT = Path(__file__).resolve().parents[3]
+CHECKOUT_MARKER = "- uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0"
+DEPENDENCY_LIFECYCLE_WORKFLOWS = (
+    ".github/workflows/security-audit.yml",
+    ".github/workflows/release.yml",
+    ".github/workflows/bandit.yml",
+)
+
+
+def _checkout_step(workflow_text: str) -> str:
+    """Return the first checkout step without accepting options from later steps."""
+    checkout_offset = workflow_text.index(CHECKOUT_MARKER)
+    checkout_tail = workflow_text[checkout_offset:]
+    next_step_offset = checkout_tail.find("\n      - ", len(CHECKOUT_MARKER))
+    if next_step_offset == -1:
+        return checkout_tail
+    return checkout_tail[:next_step_offset]
+
+
+def test_dependency_workflow_checkout_does_not_persist_github_credentials() -> None:
+    """Dependency lifecycle code must not inherit persisted checkout credentials."""
+    for workflow_path in DEPENDENCY_LIFECYCLE_WORKFLOWS:
+        workflow_text = (REPOSITORY_ROOT / workflow_path).read_text(encoding="utf-8")
+        checkout_step = _checkout_step(workflow_text)
+
+        assert "persist-credentials: false" in checkout_step, workflow_path
+
+
+def test_checkout_step_does_not_accept_credentials_from_a_later_step() -> None:
+    """A later step option must not satisfy the checkout credential contract."""
+    workflow_text = f"""steps:
+      {CHECKOUT_MARKER}
+      - uses: actions/setup-node@example
+        with:
+          persist-credentials: false
+"""
+
+    assert "persist-credentials: false" not in _checkout_step(workflow_text)