diff --git a/client/pyproject.toml b/client/pyproject.toml
index f799646..b314849 100644
--- a/client/pyproject.toml
+++ b/client/pyproject.toml
@@ -33,7 +33,7 @@ certgrinder = "certgrinder.certgrinder:main"
 
 [project.optional-dependencies]
 dev = ["twine == 5.1.0", "pre-commit == 3.7.1", "setuptools-scm == 8.1.0", "build==1.2.1"]
-test = ["pytest == 8.2.2", "pytest-cov==5.0.0", "tox == 4.15.1"]
+test = ["pytest == 8.2.2", "pytest-cov==5.0.0", "tox == 4.16.0"]
 docs = ["Sphinx==7.3.7", "sphinx-rtd-theme==2.0.0", "sphinx-argparse==0.4.0"]
 
 [project.urls]