diff --git a/etc/requirements.txt b/etc/requirements.txt
index c2ce92f30a158affd69c372af3ef1af5b85f398d..60efb73742dfd6331752b1157a52c32f17ad4b10 100644
--- a/etc/requirements.txt
+++ b/etc/requirements.txt
@@ -23,7 +23,7 @@ docutils==0.17.1
 dominate==2.6.0
 email-validator==1.1.2
 filelock==3.0.12
-Flask==2.0.0
+Flask==1.1.4
 Flask-Admin==1.5.8
 Flask-BS4==4.5.3.0
 Flask-Caching==1.10.1
@@ -40,10 +40,10 @@ identify==2.2.4
 idna==2.10
 imagesize==1.2.0
 iniconfig==1.1.1
-itsdangerous==2.0.0
+itsdangerous==1.1.0
 jaraco.context==4.0.0
 jaraco.functools==3.2.1
-Jinja2==3.0.0
+Jinja2==2.11.3
 joblib==1.0.1
 jsonpatch==1.28
 jsonpointer==2.0
@@ -53,7 +53,7 @@ kombu==5.0.2
 llvmlite==0.35.0
 Mako==1.1.4
 Markdown==3.3.3
-MarkupSafe==2.0.0
+MarkupSafe==1.1.1
 matplotlib==3.3.4
 mirakuru==2.3.0
 more-itertools==8.0.2
@@ -68,6 +68,7 @@ Pillow==8.2.0
 pip-licenses==3.3.1
 pip-tools==6.1.0
 pipenv==2020.11.15
+pkg-resources==0.0.0
 plantuml==0.3.0
 plantuml-gentools==0.1.2
 plantuml-markdown==3.4.2
@@ -114,7 +115,7 @@ simplejson==3.17.2
 six==1.16.0
 snowballstemmer==2.1.0
 speaklater==1.3
-Sphinx==3.4.3
+Sphinx==4.0.1
 sphinxcontrib-applehelp==1.0.2
 sphinxcontrib-devhelp==1.0.2
 sphinxcontrib-github==0.1.3
@@ -146,6 +147,6 @@ visdom==0.1.8.9
 visitor==0.1.3
 wcwidth==0.1.8
 websocket-client==0.57.0
-Werkzeug==2.0.1
+Werkzeug==1.0.1
 wget==3.2
 WTForms==2.3.3