diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index 32a7ccc8..ecdace00
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,3 +9,4 @@ scipy>=1.0.0
 gdal>=2.1
 numba
 pyproj
+networkx>=2.6 # not directly required, pinned by Snyk to avoid a vulnerability