diff --git a/constraints.txt b/constraints.txt
index 692431e8ff..8f70c61348 100644
--- a/constraints.txt
+++ b/constraints.txt
@@ -23,7 +23,7 @@ netifaces==0.11.0
 packaging==26.0
 patool==4.0.4
 pluggy==1.6.0
-prometheus_client==0.21.1
+prometheus_client==0.25.0
 psutil==7.0.0
 psycopg2==2.9.10
 pycryptodomex==3.23.0
diff --git a/pyproject.toml b/pyproject.toml
index 7cabb1ba1e..297e4ea26a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -40,7 +40,7 @@ dependencies = [
     "pyyaml>=5.3,<6.1",       # http://pyyaml.org/wiki/PyYAML
 
     # Only for cmsPrometheusExporter
-    "prometheus-client>=0.7,<0.22",  # https://pypi.org/project/prometheus-client
+    "prometheus-client>=0.7,<0.26",  # https://pypi.org/project/prometheus-client
 
     # Only for cmsTelegramBot
     "python-telegram-bot>=21.9,<21.12", # https://pypi.org/project/python-telegram-bot