diff --git a/.github/workflows/check-tag.yml b/.github/workflows/check-tag.yml
index 05954db..037f956 100644
--- a/.github/workflows/check-tag.yml
+++ b/.github/workflows/check-tag.yml
@@ -9,7 +9,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
       - name: Run checks
         run: |
           grep -P --color=always "\s+(?<=rev: )$GITHUB_REF_NAME$" README.md
diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 65cba0c..1a10b74 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -10,7 +10,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
       # No caching as we're expected to run rarely
       - name: Install dependencies and run checks
         run: |