diff --git a/.ci_support/environment-docs.yml b/.ci_support/environment-docs.yml
index a1ce59ba..33c2da6e 100644
--- a/.ci_support/environment-docs.yml
+++ b/.ci_support/environment-docs.yml
@@ -16,5 +16,5 @@ dependencies:
 - jupyter-book =1.0.0
 - mpi4py =4.1.1
 - python =3.12
-- pydantic =2.13.3
+- pydantic =2.13.4
 - pyzmq =27.1.0
diff --git a/.ci_support/environment-integration.yml b/.ci_support/environment-integration.yml
index e9ed1240..8be209a3 100644
--- a/.ci_support/environment-integration.yml
+++ b/.ci_support/environment-integration.yml
@@ -17,7 +17,7 @@ dependencies:
 - ipython =9.9.0
 - matplotlib =3.10.8
 - networkx =3.6.1
-- pydantic =2.13.3
+- pydantic =2.13.4
 - pygraphviz =1.14
 - pysqa =0.4.1
 - pyzmq =27.1.0
diff --git a/.ci_support/environment-mpich.yml b/.ci_support/environment-mpich.yml
index 8de9d6bc..7dd384b6 100644
--- a/.ci_support/environment-mpich.yml
+++ b/.ci_support/environment-mpich.yml
@@ -11,7 +11,7 @@ dependencies:
 - ipython =9.9.0
 - mpi4py =4.1.1
 - networkx =3.6.1
-- pydantic =2.13.3
+- pydantic =2.13.4
 - pygraphviz =1.14
 - pysqa =0.4.1
 - pyzmq =27.1.0
diff --git a/.ci_support/environment-openmpi.yml b/.ci_support/environment-openmpi.yml
index caba1393..3dde66fb 100644
--- a/.ci_support/environment-openmpi.yml
+++ b/.ci_support/environment-openmpi.yml
@@ -11,7 +11,7 @@ dependencies:
 - ipython =9.9.0
 - mpi4py =4.1.1
 - networkx =3.6.1
-- pydantic =2.13.3
+- pydantic =2.13.4
 - pygraphviz =1.14
 - pysqa =0.4.1
 - pyzmq =27.1.0
diff --git a/.ci_support/environment-win.yml b/.ci_support/environment-win.yml
index 4117fd53..9044a52a 100644
--- a/.ci_support/environment-win.yml
+++ b/.ci_support/environment-win.yml
@@ -11,6 +11,6 @@ dependencies:
 - ipython =9.9.0
 - mpi4py =4.1.1
 - networkx =3.6.1
-- pydantic =2.13.3
+- pydantic =2.13.4
 - pygraphviz =1.14
 - pyzmq =27.1.0
diff --git a/pyproject.toml b/pyproject.toml
index a7f302c0..47f04e28 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -56,13 +56,13 @@ cluster = [
     "h5py==3.16.0",
 ]
 validation = [
-    "pydantic==2.13.3",
+    "pydantic==2.13.4",
 ]
 all = [
     "mpi4py==4.1.1",
     "pysqa==0.4.1",
     "h5py==3.16.0",
-    "pydantic==2.13.3",
+    "pydantic==2.13.4",
     "pygraphviz==1.14",
     "networkx==3.6.1",
     "ipython==9.9.0",