diff --git a/poetry.lock b/poetry.lock
index b0618fda..42354e29 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -487,19 +487,20 @@ python-versions = "*"
 
 [[package]]
 name = "sphinx"
-version = "3.5.3"
+version = "4.0.1"
 description = "Python documentation generator"
 category = "dev"
 optional = false
-python-versions = ">=3.5"
+python-versions = ">=3.6"
 
 [package.dependencies]
 alabaster = ">=0.7,<0.8"
 babel = ">=1.3"
 colorama = {version = ">=0.3.5", markers = "sys_platform == \"win32\""}
-docutils = ">=0.12"
+docutils = ">=0.14,<0.18"
 imagesize = "*"
-Jinja2 = ">=2.3"
+Jinja2 = ">=2.3,<3.0"
+MarkupSafe = "<2.0"
 packaging = "*"
 Pygments = ">=2.0"
 requests = ">=2.5.0"
@@ -643,7 +644,7 @@ python-versions = "*"
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7.0"
-content-hash = "922ce10853fcbf50d16f90bab69a5a3c603c5aadbd9b969e2e9956fbe9c80ab3"
+content-hash = "6c1deb8d6dd6eae8d75575983b177c16b0b61ab3795d209841b532183438af03"
 
 [metadata.files]
 alabaster = [
@@ -871,32 +872,45 @@ lxml = [
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     {file = "lxml-4.6.3-cp27-cp27mu-manylinux1_i686.whl", hash = "sha256:7728e05c35412ba36d3e9795ae8995e3c86958179c9770e65558ec3fdfd3724f"},
     {file = "lxml-4.6.3-cp27-cp27mu-manylinux1_x86_64.whl", hash = "sha256:4bff24dfeea62f2e56f5bab929b4428ae6caba2d1eea0c2d6eb618e30a71e6d4"},
+    {file = "lxml-4.6.3-cp35-cp35m-manylinux1_i686.whl", hash = "sha256:74f7d8d439b18fa4c385f3f5dfd11144bb87c1da034a466c5b5577d23a1d9b51"},
+    {file = "lxml-4.6.3-cp35-cp35m-manylinux1_x86_64.whl", hash = "sha256:f90ba11136bfdd25cae3951af8da2e95121c9b9b93727b1b896e3fa105b2f586"},
+    {file = "lxml-4.6.3-cp35-cp35m-manylinux2010_i686.whl", hash = "sha256:4c61b3a0db43a1607d6264166b230438f85bfed02e8cff20c22e564d0faff354"},
+    {file = "lxml-4.6.3-cp35-cp35m-manylinux2014_x86_64.whl", hash = "sha256:5c8c163396cc0df3fd151b927e74f6e4acd67160d6c33304e805b84293351d16"},
     {file = "lxml-4.6.3-cp35-cp35m-win32.whl", hash = "sha256:f2380a6376dfa090227b663f9678150ef27543483055cc327555fb592c5967e2"},
     {file = "lxml-4.6.3-cp35-cp35m-win_amd64.whl", hash = "sha256:c4f05c5a7c49d2fb70223d0d5bcfbe474cf928310ac9fa6a7c6dddc831d0b1d4"},
     {file = "lxml-4.6.3-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:d2e35d7bf1c1ac8c538f88d26b396e73dd81440d59c1ef8522e1ea77b345ede4"},
     {file = "lxml-4.6.3-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:289e9ca1a9287f08daaf796d96e06cb2bc2958891d7911ac7cae1c5f9e1e0ee3"},
     {file = "lxml-4.6.3-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:bccbfc27563652de7dc9bdc595cb25e90b59c5f8e23e806ed0fd623755b6565d"},
+    {file = "lxml-4.6.3-cp36-cp36m-manylinux2010_i686.whl", hash = "sha256:d916d31fd85b2f78c76400d625076d9124de3e4bda8b016d25a050cc7d603f24"},
     {file = "lxml-4.6.3-cp36-cp36m-manylinux2014_aarch64.whl", hash = "sha256:820628b7b3135403540202e60551e741f9b6d3304371712521be939470b454ec"},
+    {file = "lxml-4.6.3-cp36-cp36m-manylinux2014_x86_64.whl", hash = "sha256:c47ff7e0a36d4efac9fd692cfa33fbd0636674c102e9e8d9b26e1b93a94e7617"},
     {file = "lxml-4.6.3-cp36-cp36m-win32.whl", hash = "sha256:5a0a14e264069c03e46f926be0d8919f4105c1623d620e7ec0e612a2e9bf1c04"},
     {file = "lxml-4.6.3-cp36-cp36m-win_amd64.whl", hash = "sha256:92e821e43ad382332eade6812e298dc9701c75fe289f2a2d39c7960b43d1e92a"},
     {file = "lxml-4.6.3-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:efd7a09678fd8b53117f6bae4fa3825e0a22b03ef0a932e070c0bdbb3a35e654"},
     {file = "lxml-4.6.3-cp37-cp37m-manylinux1_i686.whl", hash = "sha256:efac139c3f0bf4f0939f9375af4b02c5ad83a622de52d6dfa8e438e8e01d0eb0"},
     {file = "lxml-4.6.3-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:0fbcf5565ac01dff87cbfc0ff323515c823081c5777a9fc7703ff58388c258c3"},
+    {file = "lxml-4.6.3-cp37-cp37m-manylinux2010_i686.whl", hash = "sha256:36108c73739985979bf302006527cf8a20515ce444ba916281d1c43938b8bb96"},
     {file = "lxml-4.6.3-cp37-cp37m-manylinux2014_aarch64.whl", hash = "sha256:122fba10466c7bd4178b07dba427aa516286b846b2cbd6f6169141917283aae2"},
+    {file = "lxml-4.6.3-cp37-cp37m-manylinux2014_x86_64.whl", hash = "sha256:cdaf11d2bd275bf391b5308f86731e5194a21af45fbaaaf1d9e8147b9160ea92"},
     {file = "lxml-4.6.3-cp37-cp37m-win32.whl", hash = "sha256:3439c71103ef0e904ea0a1901611863e51f50b5cd5e8654a151740fde5e1cade"},
     {file = "lxml-4.6.3-cp37-cp37m-win_amd64.whl", hash = "sha256:4289728b5e2000a4ad4ab8da6e1db2e093c63c08bdc0414799ee776a3f78da4b"},
     {file = "lxml-4.6.3-cp38-cp38-macosx_10_9_x86_64.whl", hash = "sha256:b007cbb845b28db4fb8b6a5cdcbf65bacb16a8bd328b53cbc0698688a68e1caa"},
     {file = "lxml-4.6.3-cp38-cp38-manylinux1_i686.whl", hash = "sha256:76fa7b1362d19f8fbd3e75fe2fb7c79359b0af8747e6f7141c338f0bee2f871a"},
     {file = "lxml-4.6.3-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:26e761ab5b07adf5f555ee82fb4bfc35bf93750499c6c7614bd64d12aaa67927"},
+    {file = "lxml-4.6.3-cp38-cp38-manylinux2010_i686.whl", hash = "sha256:e1cbd3f19a61e27e011e02f9600837b921ac661f0c40560eefb366e4e4fb275e"},
     {file = "lxml-4.6.3-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:66e575c62792c3f9ca47cb8b6fab9e35bab91360c783d1606f758761810c9791"},
+    {file = "lxml-4.6.3-cp38-cp38-manylinux2014_x86_64.whl", hash = "sha256:1b38116b6e628118dea5b2186ee6820ab138dbb1e24a13e478490c7db2f326ae"},
     {file = "lxml-4.6.3-cp38-cp38-win32.whl", hash = "sha256:89b8b22a5ff72d89d48d0e62abb14340d9e99fd637d046c27b8b257a01ffbe28"},
     {file = "lxml-4.6.3-cp38-cp38-win_amd64.whl", hash = "sha256:2a9d50e69aac3ebee695424f7dbd7b8c6d6eb7de2a2eb6b0f6c7db6aa41e02b7"},
     {file = "lxml-4.6.3-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:ce256aaa50f6cc9a649c51be3cd4ff142d67295bfc4f490c9134d0f9f6d58ef0"},
     {file = "lxml-4.6.3-cp39-cp39-manylinux1_i686.whl", hash = "sha256:7610b8c31688f0b1be0ef882889817939490a36d0ee880ea562a4e1399c447a1"},
     {file = "lxml-4.6.3-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:f8380c03e45cf09f8557bdaa41e1fa7c81f3ae22828e1db470ab2a6c96d8bc23"},
+    {file = "lxml-4.6.3-cp39-cp39-manylinux2010_i686.whl", hash = "sha256:3082c518be8e97324390614dacd041bb1358c882d77108ca1957ba47738d9d59"},
     {file = "lxml-4.6.3-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:884ab9b29feaca361f7f88d811b1eea9bfca36cf3da27768d28ad45c3ee6f969"},
+    {file = "lxml-4.6.3-cp39-cp39-manylinux2014_x86_64.whl", hash = "sha256:6f12e1427285008fd32a6025e38e977d44d6382cf28e7201ed10d6c1698d2a9a"},
     {file = "lxml-4.6.3-cp39-cp39-win32.whl", hash = "sha256:33bb934a044cf32157c12bfcfbb6649807da20aa92c062ef51903415c704704f"},
     {file = "lxml-4.6.3-cp39-cp39-win_amd64.whl", hash = "sha256:542d454665a3e277f76954418124d67516c5f88e51a900365ed54a9806122b83"},
+    {file = "lxml-4.6.3.tar.gz", hash = "sha256:39b78571b3b30645ac77b95f7c69d1bffc4cf8c3b157c435a34da72e78c82468"},
 ]
 markupsafe = [
     {file = "MarkupSafe-1.1.1-cp27-cp27m-macosx_10_6_intel.whl", hash = "sha256:09027a7803a62ca78792ad89403b1b7a73a01c8cb65909cd876f7fcebd79b161"},
@@ -1079,8 +1093,8 @@ snowballstemmer = [
     {file = "snowballstemmer-2.1.0.tar.gz", hash = "sha256:e997baa4f2e9139951b6f4c631bad912dfd3c792467e2f03d7239464af90e914"},
 ]
 sphinx = [
-    {file = "Sphinx-3.5.3-py3-none-any.whl", hash = "sha256:3f01732296465648da43dec8fb40dc451ba79eb3e2cc5c6d79005fd98197107d"},
-    {file = "Sphinx-3.5.3.tar.gz", hash = "sha256:ce9c228456131bab09a3d7d10ae58474de562a6f79abb3dc811ae401cf8c1abc"},
+    {file = "Sphinx-4.0.1-py3-none-any.whl", hash = "sha256:b2566f5f339737a6ef37198c47d56de1f4a746c722bebdb2fe045c34bfd8b9d0"},
+    {file = "Sphinx-4.0.1.tar.gz", hash = "sha256:cf5104777571b2b7f06fa88ee08fade24563f4a0594cf4bd17d31c47b8740b4c"},
 ]
 sphinxcontrib-applehelp = [
     {file = "sphinxcontrib-applehelp-1.0.2.tar.gz", hash = "sha256:a072735ec80e7675e3f432fcae8610ecf509c5f1869d17e2eecff44389cdbc58"},
diff --git a/pyproject.toml b/pyproject.toml
index fcf6326d..e25c27e8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,7 +43,7 @@ python-gvm = ">=20.0,<22.0"
 [tool.poetry.dev-dependencies]
 autohooks = "^2.2.0"
 autohooks-plugin-pylint = "^1.2.0"
-sphinx = "^3.5.3"
+sphinx = "^4.0.1"
 pylint = "^2.7.2"
 coverage = "^5.5"
 autohooks-plugin-black = {version = "^1.2.0", python = "^3.6"}