diff --git a/kasa/smart/modules/firmware.py b/kasa/smart/modules/firmware.py
@@ -6,10 +6,12 @@
 import logging
 from asyncio import timeout as asyncio_timeout
 from collections.abc import Callable, Coroutine
+from dataclasses import dataclass, field
 from datetime import date
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Annotated
 
-from pydantic.v1 import BaseModel, Field, validator
+from mashumaro import DataClassDictMixin, field_options
+from mashumaro.types import Alias
 
 from ...exceptions import KasaException
 from ...feature import Feature
@@ -22,36 +24,36 @@
 _LOGGER = logging.getLogger(__name__)
 
 
-class DownloadState(BaseModel):
+@dataclass
+class DownloadState(DataClassDictMixin):
     """Download state."""
 
     # Example:
     #   {'status': 0, 'download_progress': 0, 'reboot_time': 5,
     #    'upgrade_time': 5, 'auto_upgrade': False}
     status: int
-    progress: int = Field(alias="download_progress")
+    progress: Annotated[int, Alias("download_progress")]
     reboot_time: int
     upgrade_time: int
     auto_upgrade: bool
 
 
-class UpdateInfo(BaseModel):
+@dataclass
+class UpdateInfo(DataClassDictMixin):
     """Update info status object."""
 
-    status: int = Field(alias="type")
-    version: str | None = Field(alias="fw_ver", default=None)
-    release_date: date | None = None
-    release_notes: str | None = Field(alias="release_note", default=None)
+    status: Annotated[int, Alias("type")]
+    needs_upgrade: Annotated[bool, Alias("need_to_upgrade")]
+    version: Annotated[str | None, Alias("fw_ver")] = None
+    release_date: date | None = field(
+        default=None,
+        metadata=field_options(
+            deserialize=lambda x: date.fromisoformat(x) if x else None
+        ),
+    )
+    release_notes: Annotated[str | None, Alias("release_note")] = None
     fw_size: int | None = None
     oem_id: str | None = None
-    needs_upgrade: bool = Field(alias="need_to_upgrade")
-
-    @validator("release_date", pre=True)
-    def _release_date_optional(cls, v: str) -> str | None:
-        if not v:
-            return None
-
-        return v
 
     @property
     def update_available(self) -> bool:
@@ -139,7 +141,7 @@ async def check_latest_firmware(self) -> UpdateInfo | None:
         """Check for the latest firmware for the device."""
         try:
             fw = await self.call("get_latest_fw")
-            self._firmware_update_info = UpdateInfo.parse_obj(fw["get_latest_fw"])
+            self._firmware_update_info = UpdateInfo.from_dict(fw["get_latest_fw"])
             return self._firmware_update_info
         except Exception:
             _LOGGER.exception("Error getting latest firmware for %s:", self._device)
@@ -174,7 +176,7 @@ async def get_update_state(self) -> DownloadState:
         """Return update state."""
         resp = await self.call("get_fw_download_state")
         state = resp["get_fw_download_state"]
-        return DownloadState(**state)
+        return DownloadState.from_dict(state)
 
     @allow_update_after
     async def update(
@@ -232,7 +234,7 @@ async def update(
                 else:
                     _LOGGER.warning("Unhandled state code: %s", state)
 
-        return state.dict()
+        return state.to_dict()
 
     @property
     def auto_update_enabled(self) -> bool:

diff --git a/tests/smart/modules/test_firmware.py b/tests/smart/modules/test_firmware.py
@@ -3,6 +3,7 @@
 import asyncio
 import logging
 from contextlib import nullcontext
+from datetime import date
 from typing import TypedDict
 
 import pytest
@@ -52,6 +53,20 @@ async def test_firmware_features(
     assert isinstance(feat.value, type)
 
 
+@firmware
+async def test_firmware_update_info(dev: SmartDevice):
+    """Test that the firmware UpdateInfo object deserializes correctly."""
+    fw = dev.modules.get(Module.Firmware)
+    assert fw
+
+    if not dev.is_cloud_connected:
+        pytest.skip("Device is not cloud connected, skipping test")
+    assert fw.firmware_update_info is None
+    await fw.check_latest_firmware()
+    assert fw.firmware_update_info is not None
+    assert isinstance(fw.firmware_update_info.release_date, date | None)
+
+
 @firmware
 async def test_update_available_without_cloud(dev: SmartDevice):
     """Test that update_available returns None when disconnected."""
@@ -105,15 +120,15 @@ class Extras(TypedDict):
     }
     update_states = [
         # Unknown 1
-        DownloadState(status=1, download_progress=0, **extras),
+        DownloadState(status=1, progress=0, **extras),
         # Downloading
-        DownloadState(status=2, download_progress=10, **extras),
-        DownloadState(status=2, download_progress=100, **extras),
+        DownloadState(status=2, progress=10, **extras),
+        DownloadState(status=2, progress=100, **extras),
         # Flashing
-        DownloadState(status=3, download_progress=100, **extras),
-        DownloadState(status=3, download_progress=100, **extras),
+        DownloadState(status=3, progress=100, **extras),
+        DownloadState(status=3, progress=100, **extras),
         # Done
-        DownloadState(status=0, download_progress=100, **extras),
+        DownloadState(status=0, progress=100, **extras),
     ]
 
     asyncio_sleep = asyncio.sleep