diff --git a/dist/restore/index.js b/dist/restore/index.js
index 9e923e1..6ea853e 100644
--- a/dist/restore/index.js
+++ b/dist/restore/index.js
@@ -60403,7 +60403,10 @@ async function run() {
         lib_core.saveState(config_STATE_BINS, JSON.stringify([...bins]));
         lib_core.info(`... Restoring cache ...`);
         const key = config.cacheKey;
-        const restoreKey = await cache.restoreCache(config.cachePaths, key, [config.restoreKey]);
+        // Pass a copy of cachePaths to avoid mutating the original array as reported by:
+        // https://github.com/actions/toolkit/pull/1378
+        // TODO: remove this once the underlying bug is fixed.
+        const restoreKey = await cache.restoreCache(config.cachePaths.slice(), key, [config.restoreKey]);
         if (restoreKey) {
             lib_core.info(`Restored from cache key "${restoreKey}".`);
             lib_core.saveState(STATE_KEY, restoreKey);
diff --git a/dist/save/index.js b/dist/save/index.js
index b1bc3cb..963ae45 100644
--- a/dist/save/index.js
+++ b/dist/save/index.js
@@ -60434,7 +60434,10 @@ async function run() {
             core.info(`[warning] ${e.stack}`);
         }
         core.info(`... Saving cache ...`);
-        await cache.saveCache(config.cachePaths, config.cacheKey);
+        // Pass a copy of cachePaths to avoid mutating the original array as reported by:
+        // https://github.com/actions/toolkit/pull/1378
+        // TODO: remove this once the underlying bug is fixed.
+        await cache.saveCache(config.cachePaths.slice(), config.cacheKey);
     }
     catch (e) {
         core.info(`[warning] ${e.stack}`);
diff --git a/src/restore.ts b/src/restore.ts
index c8320d2..f1280ca 100644
--- a/src/restore.ts
+++ b/src/restore.ts
@@ -34,7 +34,10 @@ async function run() {
 
     core.info(`... Restoring cache ...`);
     const key = config.cacheKey;
-    const restoreKey = await cache.restoreCache(config.cachePaths, key, [config.restoreKey]);
+    // Pass a copy of cachePaths to avoid mutating the original array as reported by:
+    // https://github.com/actions/toolkit/pull/1378
+    // TODO: remove this once the underlying bug is fixed.
+    const restoreKey = await cache.restoreCache(config.cachePaths.slice(), key, [config.restoreKey]);
     if (restoreKey) {
       core.info(`Restored from cache key "${restoreKey}".`);
       core.saveState(STATE_KEY, restoreKey);
diff --git a/src/save.ts b/src/save.ts
index 583e15d..7882120 100644
--- a/src/save.ts
+++ b/src/save.ts
@@ -66,7 +66,10 @@ async function run() {
     }
 
     core.info(`... Saving cache ...`);
-    await cache.saveCache(config.cachePaths, config.cacheKey);
+    // Pass a copy of cachePaths to avoid mutating the original array as reported by:
+    // https://github.com/actions/toolkit/pull/1378
+    // TODO: remove this once the underlying bug is fixed.
+    await cache.saveCache(config.cachePaths.slice(), config.cacheKey);
   } catch (e) {
     core.info(`[warning] ${(e as any).stack}`);
   }