diff --git a/requirements.txt b/requirements.txt
index 65216540..a1a9d904 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,4 +2,5 @@ requests~=2.23.0
 pytz~=2021.1
 setuptools~=49.2.0
 matplotlib~=3.1.2
-PyMuPDF~=1.18.6
\ No newline at end of file
+PyMuPDF~=1.18.6
+urllib3>=1.26.5 # not directly required, pinned by Snyk to avoid a vulnerability
\ No newline at end of file