diff --git a/poetry.lock b/poetry.lock
index 56bbf8b..c3cb7ae 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -763,13 +763,13 @@ zstd = ["zstandard (>=0.18.0)"]
 
 [[package]]
 name = "ics"
-version = "0.7.2"
+version = "0.7.3"
 description = "Python icalendar (rfc5545) parser"
 optional = false
 python-versions = "*"
 files = [
-    {file = "ics-0.7.2-py2.py3-none-any.whl", hash = "sha256:5fcf4d29ec6e7dfcb84120abd617bbba632eb77b097722b7df70e48dbcf26103"},
-    {file = "ics-0.7.2.tar.gz", hash = "sha256:6743539bca10391635249b87d74fcd1094af20b82098bebf7c7521df91209f05"},
+    {file = "ics-0.7.3-py2.py3-none-any.whl", hash = "sha256:519f633f2e3d7b1528847e990a58dcb8807a2fffdcfd9dd880d1d5094d456af7"},
+    {file = "ics-0.7.3.tar.gz", hash = "sha256:2dcd6876e8c913d40db76f1f1ca47bccd1c162178c73f69fbbedca1b844eface"},
 ]
 
 [package.dependencies]
@@ -777,7 +777,7 @@ arrow = ">=0.11"
 attrs = ">=19.1.0"
 python-dateutil = "*"
 six = ">1.5"
-tatsu = ">4.2"
+tatsu = ">4.2,<5.16.0"
 
 [[package]]
 name = "idna"
@@ -2893,4 +2893,4 @@ type = ["pytest-mypy"]
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.10"
-content-hash = "908290fe9752989522db32ad79113391e31458906f1c91e1994d30e6d048d23f"
+content-hash = "f0f2c9a555bd1c067ffef079ba2dde41a6fef12c74640336ff21609a9e97000a"
diff --git a/pyproject.toml b/pyproject.toml
index b3e0f7c..69202ed 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -13,7 +13,7 @@ python = "^3.10"
 fastapi = {version = "0.110.1", extras = ["all"]}
 requests = "2.31.0"
 cachetools = "^5.3.1"
-ics = "0.7.2"
+ics = "0.7.3"
 arrow = "1.3.0"
 prometheus-client = "0.20.0"
 prometheus-fastapi-instrumentator = "7.0.0"