diff --git a/pyproject.toml b/pyproject.toml
index ada0c40..0b31320 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,7 +15,7 @@ dependencies = ["salt"]
 test = ["pylint==3.3.1", "pytest==8.3.3"]
 
 [tool.pdm.dev-dependencies]
-dev = ["pylint==3.3.1", "pytest==8.3.3", "ruff==0.6.8", "tox==4.20.0"]
+dev = ["pylint==3.3.1", "pytest==8.3.3", "ruff==0.6.8", "tox==4.21.2"]
 
 [tool.pdm.resolution.overrides]
 pyzmq = "~=25.1" # 25.0.2 does not compile on 24.04 anymore