diff --git a/.github/workflows/phpunit.yml b/.github/workflows/phpunit.yml
index 6cdce10d19..9d2e2beb65 100644
--- a/.github/workflows/phpunit.yml
+++ b/.github/workflows/phpunit.yml
@@ -33,6 +33,8 @@ jobs:
       TESTS_ZEND_CACHE_LIBMEMCACHED_HOST: 127.0.0.1
       TESTS_ZEND_CACHE_LIBMEMCACHED_PORT: 11211
 
+      TESTS_ZEND_CACHE_APC_ENABLED: true
+
       # https://hub.docker.com/r/bitnami/openldap
       LDAP_ROOT: "dc=example,dc=com"
       LDAP_ALLOW_ANON_BINDING: false
@@ -112,15 +114,15 @@ jobs:
           #bare for PHP >=7.2
           - php-extensions-bare: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring"
           #full for PHP <= 8.0
-          - php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt, rar"
+          - php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, apcu, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt, rar"
           - php-version: "7.1"
             php-extensions-bare: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer"
           - php-version: "8.1"
-            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt"
+            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, apcu, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt"
           - php-version: "8.2"
-            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt"
+            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, apcu, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite, mcrypt"
           - php-version: "8.3"
-            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite"
+            php-extensions-full: "none, iconv, json, libxml, xml, dom, simplexml, xmlwriter, tokenizer, mbstring, apcu, ctype, openssl, curl, gd, posix, pdo_sqlite, pdo_mysql, fileinfo, zip, sqlite, soap, bcmath, igbinary, bz2, lzf, memcached, memcache, ldap, sqlite"
             experimental: true
 
     steps:
@@ -181,7 +183,7 @@ jobs:
           php-version: ${{ matrix.php-version }}
           tools: cs2pr
           extensions: ${{ matrix.php-extensions-full }}
-          ini-values: ${{ env.PHP_INI_VALUES }}
+          ini-values: ${{ env.PHP_INI_VALUES }}, apc.enable_cli=1
         env:
           # https://github.com/shivammathur/setup-php/issues/407#issuecomment-773675741
           fail-fast: true
diff --git a/library/Zend/Cache/Backend/Apc.php b/library/Zend/Cache/Backend/Apc.php
index 4f70b44b3c..bbd623f912 100644
--- a/library/Zend/Cache/Backend/Apc.php
+++ b/library/Zend/Cache/Backend/Apc.php
@@ -74,8 +74,9 @@ public function load($id, $doNotTestCacheValidity = false)
     {
         $tmp = apcu_fetch($id);
         if (is_array($tmp)) {
-            return $tmp[0];
+            return $tmp[0] ?? false;
         }
+        apcu_delete($id);
         return false;
     }
 
@@ -89,7 +90,7 @@ public function test($id)
     {
         $tmp = apcu_fetch($id);
         if (is_array($tmp)) {
-            return $tmp[1];
+            return $tmp[1] ?? false;
         }
         return false;
     }
diff --git a/library/Zend/Cache/Backend/TwoLevels.php b/library/Zend/Cache/Backend/TwoLevels.php
index 9cb04094b2..7f07388d81 100644
--- a/library/Zend/Cache/Backend/TwoLevels.php
+++ b/library/Zend/Cache/Backend/TwoLevels.php
@@ -230,17 +230,33 @@ public function save($data, $id, $tags = [], $specificLifetime = false, $priorit
     public function load($id, $doNotTestCacheValidity = false)
     {
         $resultFast = $this->_fastBackend->load($id, $doNotTestCacheValidity);
-        if ($resultFast === false) {
+        $array = null;
+        $isFastResult = is_string($resultFast);
+        if ($isFastResult) {
+            $array = unserialize($resultFast, ['allowed_classes' => false]);
+        }
+        if (!is_array($array)) {
+            if ($isFastResult) {
+                // If the fast result data is not an array, it means it got corrupted somehow at rest.
+                // Remove it before trying the slow one.
+                $this->_fastBackend->remove($id);
+            }
             $resultSlow = $this->_slowBackend->load($id, $doNotTestCacheValidity);
-            if ($resultSlow === false) {
+            if (!is_string($resultSlow)) {
                 // there is no cache at all for this id
                 return false;
             }
+            $array = unserialize($resultSlow, ['allowed_classes' => false]);
+            if (!is_array($array)) {
+                // If the slow result data is not an array, it means it got corrupted somehow at rest.
+                // Remove it and return false.
+                $this->_slowBackend->remove($id);
+                return false;
+            }
         }
-        $array = $resultFast !== false ? unserialize($resultFast) : unserialize($resultSlow);
 
         //In case no cache entry was found in the FastCache and auto-filling is enabled, copy data to FastCache
-        if ($resultFast === false && $this->_options['auto_fill_fast_cache']) {
+        if (!$isFastResult && $this->_options['auto_fill_fast_cache']) {
             $preparedData = $this->_prepareData($array['data'], $array['lifetime'], $array['priority']);
             $this->_fastBackend->save($preparedData, $id, [], $array['lifetime']);
         }
@@ -461,7 +477,7 @@ public function getCapabilities()
     }
 
     /**
-     * Prepare a serialized array to store datas and metadatas informations
+     * Prepare a serialized array to store data and metadata information
      *
      * @param string $data data to store
      * @param int $lifetime original lifetime
diff --git a/tests/Zend/Cache/AllTests.php b/tests/Zend/Cache/AllTests.php
index c7d419b2ef..b132a33dcd 100644
--- a/tests/Zend/Cache/AllTests.php
+++ b/tests/Zend/Cache/AllTests.php
@@ -104,9 +104,9 @@ public static function suite()
             $skipTest = new Zend_Cache_ApcBackendTest_SkipTests();
             $skipTest->message = 'Tests are not enabled in TestConfiguration.php';
             $suite->addTest($skipTest);
-        } elseif (!extension_loaded('apc')) {
+        } elseif (!extension_loaded('apcu')) {
             $skipTest = new Zend_Cache_ApcBackendTest_SkipTests();
-            $skipTest->message = "Extension 'APC' is not loaded";
+            $skipTest->message = "Extension 'apcu' is not loaded";
             $suite->addTest($skipTest);
         } else {
             $suite->addTestSuite('Zend_Cache_ApcBackendTest');
@@ -218,9 +218,9 @@ public static function suite()
             $skipTest = new Zend_Cache_TwoLevelsBackendTest_SkipTests();
             $skipTest->message = 'Tests are not enabled in TestConfiguration.php';
             $suite->addTest($skipTest);
-        } elseif (!extension_loaded('apc')) {
+        } elseif (!extension_loaded('apcu')) {
             $skipTest = new Zend_Cache_TwoLevelsBackendTest_SkipTests();
-            $skipTest->message = "Extension 'APC' is not loaded";
+            $skipTest->message = "Extension 'apcu' is not loaded";
             $suite->addTest($skipTest);
         } else {
             $suite->addTestSuite('Zend_Cache_TwoLevelsBackendTest');
diff --git a/tests/Zend/Cache/ApcBackendTest.php b/tests/Zend/Cache/ApcBackendTest.php
index c1e66d6ba7..f4cef0c261 100644
--- a/tests/Zend/Cache/ApcBackendTest.php
+++ b/tests/Zend/Cache/ApcBackendTest.php
@@ -175,9 +175,6 @@ public function testGetTags()
     {
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveCorrectCall()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -185,9 +182,6 @@ public function testSaveCorrectCall()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithNullLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -195,9 +189,6 @@ public function testSaveWithNullLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithSpecificLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -205,9 +196,6 @@ public function testSaveWithSpecificLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testGetMetadatas($notag = true)
     {
         parent::testGetMetadatas($notag);
diff --git a/tests/Zend/Cache/WinCacheBackendTest.php b/tests/Zend/Cache/WinCacheBackendTest.php
index 15fcf0868a..d9b9ea243e 100644
--- a/tests/Zend/Cache/WinCacheBackendTest.php
+++ b/tests/Zend/Cache/WinCacheBackendTest.php
@@ -198,9 +198,6 @@ public function testGetTags()
         $this->markTestSkipped('This test skipped due to limitations in this adapter.');
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveCorrectCall()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -208,9 +205,6 @@ public function testSaveCorrectCall()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithNullLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -218,9 +212,6 @@ public function testSaveWithNullLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithSpecificLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -228,9 +219,6 @@ public function testSaveWithSpecificLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testGetMetadatas($notag = true)
     {
         parent::testGetMetadatas($notag);
diff --git a/tests/Zend/Cache/XcacheBackendTest.php b/tests/Zend/Cache/XcacheBackendTest.php
index 0147128e6a..69be8afae7 100644
--- a/tests/Zend/Cache/XcacheBackendTest.php
+++ b/tests/Zend/Cache/XcacheBackendTest.php
@@ -129,9 +129,7 @@ public function testCleanModeNotMatchingTags2()
     public function testCleanModeNotMatchingTags3()
     {
     }
-    /**
-     * @doesNotPerformAssertions
-     */
+
     public function testSaveCorrectCall()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -139,9 +137,6 @@ public function testSaveCorrectCall()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithNullLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -149,9 +144,6 @@ public function testSaveWithNullLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithSpecificLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
diff --git a/tests/Zend/Cache/ZendServerDiskTest.php b/tests/Zend/Cache/ZendServerDiskTest.php
index 5d1e26cd43..809eaccc14 100755
--- a/tests/Zend/Cache/ZendServerDiskTest.php
+++ b/tests/Zend/Cache/ZendServerDiskTest.php
@@ -126,9 +126,7 @@ public function testCleanModeNotMatchingTags2()
     public function testCleanModeNotMatchingTags3()
     {
     }
-    /**
-     * @doesNotPerformAssertions
-     */
+
     public function testSaveCorrectCall()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -136,9 +134,6 @@ public function testSaveCorrectCall()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithNullLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -146,9 +141,6 @@ public function testSaveWithNullLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithSpecificLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
diff --git a/tests/Zend/Cache/ZendServerShMemTest.php b/tests/Zend/Cache/ZendServerShMemTest.php
index 4da810fc77..ac532a2ac3 100755
--- a/tests/Zend/Cache/ZendServerShMemTest.php
+++ b/tests/Zend/Cache/ZendServerShMemTest.php
@@ -126,9 +126,7 @@ public function testCleanModeNotMatchingTags2()
     public function testCleanModeNotMatchingTags3()
     {
     }
-    /**
-     * @doesNotPerformAssertions
-     */
+
     public function testSaveCorrectCall()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -136,9 +134,6 @@ public function testSaveCorrectCall()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithNullLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);
@@ -146,9 +141,6 @@ public function testSaveWithNullLifeTime()
         $this->_instance->setDirectives(['logging' => true]);
     }
 
-    /**
-     * @doesNotPerformAssertions
-     */
     public function testSaveWithSpecificLifeTime()
     {
         $this->_instance->setDirectives(['logging' => false]);