diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d0231adf..4e6a6caf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -292,7 +292,7 @@ jobs:
         with:
           toolchain: stable
           components: llvm-tools-preview
-      - uses: taiki-e/install-action@94c31af3204a9f15ab40b35ad084410b905bbc73  # v2.87.17
+      - uses: taiki-e/install-action@83ac0ad63c0167e6f06796fab0fce28db1bf3db0  # v2.87.22
         with:
           tool: cargo-llvm-cov
       - uses: Swatinem/rust-cache@f0d9c3887740aee45f6153b24b3a6b815192ec16  # v2
@@ -394,7 +394,7 @@ jobs:
           # Need full history so `git diff origin/<base_ref>...HEAD` can resolve the
           # base ref (used by --in-diff to scope mutation testing to changed lines).
           fetch-depth: 0
-      - uses: taiki-e/install-action@94c31af3204a9f15ab40b35ad084410b905bbc73  # v2.87.17
+      - uses: taiki-e/install-action@83ac0ad63c0167e6f06796fab0fce28db1bf3db0  # v2.87.22
         with:
           # cycle-006: tightened from major-only @27 to the exact release @27.1.0 —
           # the aggregator now depends on outcomes.json's schema being stable across
@@ -520,7 +520,7 @@ jobs:
         # fetch-depth: 0 is NOT needed here — the diff was already computed
         # once in mutants-plan and is downloaded below, not recomputed.
 
-      - uses: taiki-e/install-action@94c31af3204a9f15ab40b35ad084410b905bbc73  # v2.87.17
+      - uses: taiki-e/install-action@83ac0ad63c0167e6f06796fab0fce28db1bf3db0  # v2.87.22
         with:
           tool: cargo-mutants@27.1.0  # same exact pin as mutants-plan
       - uses: Swatinem/rust-cache@f0d9c3887740aee45f6153b24b3a6b815192ec16  # v2
diff --git a/.github/workflows/mutants-nightly.yml b/.github/workflows/mutants-nightly.yml
index 6afe3dda..a5122dd9 100644
--- a/.github/workflows/mutants-nightly.yml
+++ b/.github/workflows/mutants-nightly.yml
@@ -61,7 +61,7 @@ jobs:
 
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
-      - uses: taiki-e/install-action@94c31af3204a9f15ab40b35ad084410b905bbc73 # v2.87.17
+      - uses: taiki-e/install-action@83ac0ad63c0167e6f06796fab0fce28db1bf3db0 # v2.87.22
         with:
           tool: cargo-mutants@27.1.0