diff --git a/fdroidserver/common.py b/fdroidserver/common.py
index 2658d4a4..403bb74d 100644
--- a/fdroidserver/common.py
+++ b/fdroidserver/common.py
@@ -3006,7 +3006,7 @@ def set_FDroidPopen_env(build=None):
     if build is not None:
         path = build.ndk_path()
         paths = orig_path.split(os.pathsep)
-        if path not in paths:
+        if path and path not in paths:
             paths = [path] + paths
             env['PATH'] = os.pathsep.join(paths)
         for n in ['ANDROID_NDK', 'NDK', 'ANDROID_NDK_HOME']:
diff --git a/tests/common.TestCase b/tests/common.TestCase
index be2a04bd..a29920be 100755
--- a/tests/common.TestCase
+++ b/tests/common.TestCase
@@ -2364,6 +2364,14 @@ class CommonTest(unittest.TestCase):
             "%s_%s.exe" % (app.id, build.versionCode),
         )
 
+    def test_no_zero_length_ndk_path_prefixes(self):
+        fdroidserver.common.config = {'ndk_paths': {}}
+        build = fdroidserver.metadata.Build()
+
+        os.environ['PATH'] = '/usr/bin:/usr/sbin'
+        fdroidserver.common.set_FDroidPopen_env(build)
+        self.assertNotIn('', os.getenv('PATH').split(os.pathsep))
+
 
 if __name__ == "__main__":
     os.chdir(os.path.dirname(__file__))