diff --git a/lib/private/legacy/util.php b/lib/private/legacy/util.php
index d201283598..d49599cb8a 100644
--- a/lib/private/legacy/util.php
+++ b/lib/private/legacy/util.php
@@ -1389,8 +1389,8 @@ class OC_Util {
 			return false;
 		}
 
-		$path_parts = pathinfo($trimmed);
-		if ($path_parts['extension'] === 'part') {
+		// detect part files
+		if (preg_match('/' . \OCP\Files\FileInfo::BLACKLIST_FILES_REGEX . '/', $trimmed) !== 0) {
 			return false;
 		}
 
diff --git a/tests/lib/UtilTest.php b/tests/lib/UtilTest.php
index 278e6cfd4c..39a29742e4 100644
--- a/tests/lib/UtilTest.php
+++ b/tests/lib/UtilTest.php
@@ -204,41 +204,51 @@ class UtilTest extends \Test\TestCase {
 	}
 
 	public function filenameValidationProvider() {
-		return array(
+		return [
 			// valid names
-			array('boringname', true),
-			array('something.with.extension', true),
-			array('now with spaces', true),
-			array('.a', true),
-			array('..a', true),
-			array('.dotfile', true),
-			array('single\'quote', true),
-			array('  spaces before', true),
-			array('spaces after   ', true),
-			array('allowed chars including the crazy ones $%&_-^@!,()[]{}=;#', true),
-			array('汉字也能用', true),
-			array('und Ümläüte sind auch willkommen', true),
+			['boringname', true],
+			['something.with.extension', true],
+			['now with spaces', true],
+			['.a', true],
+			['..a', true],
+			['.dotfile', true],
+			['single\'quote', true],
+			['  spaces before', true],
+			['spaces after   ', true],
+			['allowed chars including the crazy ones $%&_-^@!,()[]{}=;#', true],
+			['汉字也能用', true],
+			['und Ümläüte sind auch willkommen', true],
 			// disallowed names
-			array('', false),
-			array('     ', false),
-			array('.', false),
-			array('..', false),
-			array('back\\slash', false),
-			array('sl/ash', false),
-			array('lt<lt', true),
-			array('gt>gt', true),
-			array('col:on', true),
-			array('double"quote', true),
-			array('pi|pe', true),
-			array('dont?ask?questions?', true),
-			array('super*star', true),
-			array('new\nline', false),
+			['', false],
+			['     ', false],
+			['.', false],
+			['..', false],
+			['back\\slash', false],
+			['sl/ash', false],
+			['lt<lt', true],
+			['gt>gt', true],
+			['col:on', true],
+			['double"quote', true],
+			['pi|pe', true],
+			['dont?ask?questions?', true],
+			['super*star', true],
+			['new\nline', false],
+
 			// better disallow these to avoid unexpected trimming to have side effects
-			array(' ..', false),
-			array('.. ', false),
-			array('. ', false),
-			array(' .', false),
-		);
+			[' ..', false],
+			['.. ', false],
+			['. ', false],
+			[' .', false],
+
+			// part files not allowed
+			['.part', false],
+			['notallowed.part', false],
+			['neither.filepart', false],
+
+			// part in the middle is ok
+			['super movie part one.mkv', true],
+			['super.movie.part.mkv', true],
+		];
 	}
 
 	/**