diff --git a/.travis.yml b/.travis.yml
index a3038c1..7408b2e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,4 +11,5 @@ install:
   - composer install
 script:
   - make clean
+  - make check_permissions
   - make test
diff --git a/Makefile b/Makefile
index a86f9aa..75c54f2 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,7 @@ BIN = vendor/bin
 PHP_SOURCE = index.php application tests plugins
 PHP_COMMA_SOURCE = index.php,application,tests,plugins
 
-all: static_analysis_summary test
+all: static_analysis_summary check_permissions test
 
 ##
 # Concise status of the project
@@ -98,6 +98,20 @@ mess_detector_summary: mess_title
 		printf "$$warnings\t$$rule\n"; \
 	done;
 
+##
+# Checks source file & script permissions
+##
+check_permissions:
+	@echo "----------------------"
+	@echo "Check file permissions"
+	@echo "----------------------"
+	@for file in `git ls-files`; do \
+		if [ -x $$file ]; then \
+			errors=true; \
+			echo "$${file} is executable"; \
+		fi \
+	done; [ -z $$errors ] || false
+
 ##
 # PHPUnit
 # Runs unitary and functional tests
diff --git a/application/HttpUtils.php b/application/HttpUtils.php
old mode 100755
new mode 100644
diff --git a/application/LinkUtils.php b/application/LinkUtils.php
old mode 100755
new mode 100644
diff --git a/application/Url.php b/application/Url.php
old mode 100755
new mode 100644
diff --git a/plugins/qrcode/qrcode.css b/plugins/qrcode/qrcode.css
old mode 100755
new mode 100644
diff --git a/tpl/tools.html b/tpl/tools.html
old mode 100755
new mode 100644