diff --git a/application/themehandler.class.inc.php b/application/themehandler.class.inc.php
index 52073bea3..25c5b6734 100644
--- a/application/themehandler.class.inc.php
+++ b/application/themehandler.class.inc.php
@@ -699,8 +699,9 @@ CSS;
 
 	/**
 	 * @since 3.0.0 N°2982
-	 * Extract the signature for a generated CSS file. The signature MUST be alone one line immediately
-	 * followed (on the next line) by the === SIGNATURE END === pattern
+	 * Extract the signature for a generated CSS file.
+	 * The signature MUST be alone one line immediately followed (on the next line) by the === SIGNATURE END === pattern
+	 * The signature MUST be in the first 100th lines of the file.
 	 *
 	 * Note the signature can be place anywhere in the CSS file (obviously inside a CSS comment !) but the
 	 * function will be faster if the signature is at the beginning of the file (since the file is scanned from the start)
@@ -711,6 +712,7 @@ CSS;
 	 */
 	public static function GetSignature($sFilepath)
 	{
+		$iCount = 0;
 		$sPreviousLine = '';
 		$hFile = @fopen($sFilepath, "r");
 		if ($hFile !== false)
@@ -718,10 +720,11 @@ CSS;
 			$sLine = '';
 			do
 			{
+				$iCount++;
 				$sPreviousLine = $sLine;
 				$sLine = rtrim(fgets($hFile)); // Remove the trailing \n
 			}
-			while (($sLine !== false) && ($sLine != '=== SIGNATURE END ==='));
+			while (($sLine !== false) && ($sLine != '=== SIGNATURE END ===') && ($iCount <= 100));
 			fclose($hFile);
 		}
 		return $sPreviousLine;
diff --git a/test/application/ThemeHandlerTest.php b/test/application/ThemeHandlerTest.php
index 2e6b6caf3..9fda00021 100644
--- a/test/application/ThemeHandlerTest.php
+++ b/test/application/ThemeHandlerTest.php
@@ -223,6 +223,13 @@ class ThemeHandlerTest extends ItopTestCase
 		return @mkdir($dir);
 	}
 
+	public function testGetSignatureWithFileWithoutSignature()
+	{
+		$sTmpFile = tempnam(sys_get_temp_dir(), "sig");
+		file_put_contents($sTmpFile,"ffff");
+		$this->assertEquals("",  ThemeHandler::GetSignature($sTmpFile));
+	}
+
 	public function testGetSignature()
 	{
 		$sSig = ThemeHandler::GetSignature(APPROOT.'test/application/theme-handler/expected/themes/basque-red/main.css');