diff --git a/doc/requirements.txt b/doc/requirements.txt
index 0f8bf5cd..3958ea11 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -3,7 +3,7 @@
 # process, which may cause wedges in the gate later.
 
 # Documentation
-sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
+sphinx>2.1.0
 oslosphinx>=4.7.0 # Apache-2.0
 sphinx_rtd_theme
 
diff --git a/tox.ini b/tox.ini
index c15d4e0f..d20d0ddf 100644
--- a/tox.ini
+++ b/tox.ini
@@ -35,7 +35,9 @@ deps =
 commands =
   bash -c "{toxinidir}/tools/gate/whitespace-linter.sh"
   bandit -r pegleg -n 5
-  safety check -r requirements.txt --bare
+  safety check -r {toxinidir}/requirements.txt \
+               -r {toxinidir}/test-requirements.txt \
+               -r {toxinidir}/doc/requirements.txt --bare
   flake8 {toxinidir}/pegleg
 whitelist_externals =
   bash
@@ -60,6 +62,7 @@ deps =
 commands =
     safety check -r {toxinidir}/requirements.txt --full-report
     safety check -r {toxinidir}/test-requirements.txt --full-report
+    safety check -r {toxinidir}/doc/requirements.txt --full-report
 
 [testenv:cover]
 basepython = python3