diff --git a/requirements.txt b/requirements.txt
index 4451fe5..c1f56ac 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -16,7 +16,7 @@ Jinja2==2.11.3
 MarkupSafe==1.1.1
 pdf2image==1.4.2
 Pillow==8.1.1
-protobuf==3.7.0
+protobuf==3.15.0
 pyasn1==0.4.5
 pyasn1-modules==0.2.4
 PyPDF2==1.26.0