diff --git a/doc/requirements.txt b/doc/requirements.txt
index 98fd8ed7..8f840549 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -106,7 +106,7 @@ stack-data==0.6.3 ; python_version >= "3.10" and python_version < "4"
 threadpoolctl==3.6.0 ; python_version >= "3.10" and python_version < "4"
 tinycss2==1.5.1 ; python_version >= "3.10" and python_version < "4"
 tomli==2.4.1 ; python_version >= "3.10" and python_version < "4"
-tornado==6.5.8 ; python_version >= "3.10" and python_version < "4"
+tornado==6.5.9 ; python_version >= "3.10" and python_version < "4"
 traitlets==5.16.1 ; python_version >= "3.10" and python_version < "4"
 typing-extensions==4.16.0 ; python_version >= "3.10" and python_version < "4"
 tzdata==2026.3 ; python_version >= "3.10" and python_version < "4" and (sys_platform == "win32" or sys_platform == "emscripten") or python_version == "3.10"