diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 55c3c99..3d9fe16 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -8,6 +8,13 @@ updates:
       actions:
         patterns:
           - "*"
+    ignore:
+      # v4.38.1 fails GitHub workflow-startup validation estate-wide
+      # (codeql.yml/hypatia-scan.yml startup_failure on every repo that merged
+      # the grouped bump; v4.38.0 is green). Rollback: PR #100. Revisit once
+      # 4.38.1 is cleared upstream.
+      - dependency-name: "github/codeql-action"
+        versions: ["4.38.1"]
   # Rust core crate. NOTE: deliberately no entry for /desktop — its path
   # dependency on an external sibling checkout (../../gossamer) would make
   # dependabot error.
diff --git a/.github/workflows/actions.lock b/.github/workflows/actions.lock
index ebb0530..c432e34 100644
--- a/.github/workflows/actions.lock
+++ b/.github/workflows/actions.lock
@@ -14,7 +14,7 @@ workflows:
         - 'haskell-actions/setup@v2.12.0'
     '.github/workflows/codeql.yml':
         - 'actions/checkout@v7.0.1'
-        - 'github/codeql-action@v4.38.0'
+        - 'github/codeql-action@b96794f015dfd88f77b49b1c93e0fa7110f94c63'
     '.github/workflows/dogfood-gate.yml':
         - 'actions/checkout@v7.0.1'
         - 'hyperpolymath/deed-ecosystem@main'
@@ -25,7 +25,7 @@ workflows:
         - 'actions/github-script@v9.0.0'
         - 'actions/upload-artifact@v7.0.1'
         - 'erlef/setup-beam@v1.24.1'
-        - 'github/codeql-action@v4.38.0'
+        - 'github/codeql-action@b96794f015dfd88f77b49b1c93e0fa7110f94c63'
     '.github/workflows/instant-sync.yml':
         - 'peter-evans/repository-dispatch@v4.0.1'
     '.github/workflows/label-triage.yml': []
@@ -88,8 +88,8 @@ dependencies:
         commit: 'sha1-54075bcc5e249e4758d363f27d099f55d843f124'
         owner_id: 47606891
         repo_id: 331103973
-    'github/codeql-action@v4.38.0':
-        ref: 'v4.38.0'
+    'github/codeql-action@b96794f015dfd88f77b49b1c93e0fa7110f94c63':
+        ref: 'b96794f015dfd88f77b49b1c93e0fa7110f94c63'
         commit: 'sha1-b96794f015dfd88f77b49b1c93e0fa7110f94c63'
         owner_id: 9919
         repo_id: 259445878
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 545c487..b6d1b6b 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -44,12 +44,12 @@ jobs:
         uses: actions/checkout@v7.0.1
 
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@v4.38.1
+        uses: github/codeql-action/init@b96794f015dfd88f77b49b1c93e0fa7110f94c63 # v4.38.0 (4.38.1 blocked estate-wide; see PR #100)
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v4.38.1
+        uses: github/codeql-action/analyze@b96794f015dfd88f77b49b1c93e0fa7110f94c63 # v4.38.0 (4.38.1 blocked estate-wide; see PR #100)
         with:
           category: "/language:${{ matrix.language }}"
diff --git a/.github/workflows/hypatia-scan.yml b/.github/workflows/hypatia-scan.yml
index 7bc31f4..5475494 100644
--- a/.github/workflows/hypatia-scan.yml
+++ b/.github/workflows/hypatia-scan.yml
@@ -245,7 +245,7 @@ jobs:
           always() &&
           (github.event_name != 'pull_request' ||
            github.event.pull_request.head.repo.fork != true)
-        uses: github/codeql-action/upload-sarif@v4.38.1
+        uses: github/codeql-action/upload-sarif@b96794f015dfd88f77b49b1c93e0fa7110f94c63 # v4.38.0 (4.38.1 blocked estate-wide; see PR #100)
         with:
           sarif_file: hypatia.sarif
           # Distinct category so Hypatia results coexist with CodeQL's