diff --git a/typo3/sysext/core/Classes/Utility/GeneralUtility.php b/typo3/sysext/core/Classes/Utility/GeneralUtility.php
index fa25704..f664d9e 100644
--- a/typo3/sysext/core/Classes/Utility/GeneralUtility.php
+++ b/typo3/sysext/core/Classes/Utility/GeneralUtility.php
@@ -3232,7 +3232,7 @@ Connection: close
 	 * Abstraction method which returns System Environment Variables regardless of server OS, CGI/MODULE version etc. Basically this is SERVER variables for most of them.
 	 * This should be used instead of getEnv() and $_SERVER/ENV_VARS to get reliable values for all situations.
 	 *
-	 * @param string $getEnvName Name of the "environment variable"/"server variable" you wish to use. Valid values are SCRIPT_NAME, SCRIPT_FILENAME, REQUEST_URI, PATH_INFO, REMOTE_ADDR, REMOTE_HOST, HTTP_REFERER, HTTP_HOST, HTTP_USER_AGENT, HTTP_ACCEPT_LANGUAGE, QUERY_STRING, TYPO3_DOCUMENT_ROOT, TYPO3_HOST_ONLY, TYPO3_HOST_ONLY, TYPO3_REQUEST_HOST, TYPO3_REQUEST_URL, TYPO3_REQUEST_SCRIPT, TYPO3_REQUEST_DIR, TYPO3_SITE_URL, _ARRAY
+	 * @param string $getEnvName Name of the "environment variable"/"server variable" you wish to use. Valid values are SCRIPT_NAME, SCRIPT_FILENAME, REQUEST_URI, PATH_INFO, REMOTE_ADDR, REMOTE_HOST, HTTP_REFERER, HTTP_HOST, HTTP_USER_AGENT, HTTP_ACCEPT_LANGUAGE, QUERY_STRING, TYPO3_DOCUMENT_ROOT, TYPO3_HOST_ONLY, TYPO3_HOST_ONLY, TYPO3_REQUEST_HOST, TYPO3_REQUEST_URL, TYPO3_REQUEST_SCRIPT, TYPO3_REQUEST_DIR, TYPO3_SITE_URL, TYPO3_DISABLE_CORE_UPDATER, _ARRAY
 	 * @return string Value based on the input key, independent of server/os environment.
 	 */
 	static public function getIndpEnv($getEnvName) {
@@ -3464,6 +3464,9 @@ Connection: close
 					$retVal = $_SERVER['SSL_SESSION_ID'] || strtolower($_SERVER['HTTPS']) === 'on' || (string)$_SERVER['HTTPS'] === '1' ? TRUE : FALSE;
 				}
 				break;
+			case 'TYPO3_DISABLE_CORE_UPDATER':
+				$retVal = self::getRedirectEnvironmentVariable($getEnvName);
+				break;
 			case '_ARRAY':
 				$out = array();
 				// Here, list ALL possible keys to this function for debug display.
@@ -3502,6 +3505,26 @@ Connection: close
 	}
 
 	/**
+	 * Returns an environment variable taking possible "REDIRECT_"
+	 * prefixes into account (e.g. due to PHP running in CGI mode)
+	 *
+	 * The given environment variable will be prefixed at maximum of 5 times.
+	 *
+	 * @param string $environmentVariable the environment variable to retrieve
+	 * @return mixed
+	 */
+	static protected function getRedirectEnvironmentVariable($environmentVariable) {
+		for ($prefixCount = 0; $prefixCount < 5; ++$prefixCount) {
+			$environmentVariableName = str_repeat('REDIRECT_', $prefixCount) . $environmentVariable;
+
+			if (isset($_SERVER[$environmentVariableName])) {
+				return $_SERVER[$environmentVariableName];
+			}
+		}
+		return NULL;
+	}
+
+	/**
 	 * Gets the unixtime as milliseconds.
 	 *
 	 * @return integer The unixtime as milliseconds
diff --git a/typo3/sysext/install/Classes/Service/CoreUpdateService.php b/typo3/sysext/install/Classes/Service/CoreUpdateService.php
index 0c8e9f2..197a865 100644
--- a/typo3/sysext/install/Classes/Service/CoreUpdateService.php
+++ b/typo3/sysext/install/Classes/Service/CoreUpdateService.php
@@ -94,7 +94,7 @@ class CoreUpdateService {
 	 * @return boolean
 	 */
 	public function isCoreUpdateEnabled() {
-		return (getenv('TYPO3_DISABLE_CORE_UPDATER') !== '1');
+		return (GeneralUtility::getIndpEnv('TYPO3_DISABLE_CORE_UPDATER') !== '1');
 	}
 
 	/**