diff --git a/libuavcan_drivers/stm32/driver/src/internal.hpp b/libuavcan_drivers/stm32/driver/src/internal.hpp
index 68ede133d4..4497bde791 100644
--- a/libuavcan_drivers/stm32/driver/src/internal.hpp
+++ b/libuavcan_drivers/stm32/driver/src/internal.hpp
@@ -34,10 +34,9 @@
 
 /**
  * Priority mask for timer and CAN interrupts.
- * Medium priority by default.
  */
 #ifndef UAVCAN_STM32_IRQ_PRIORITY_MASK
-# define UAVCAN_STM32_IRQ_PRIORITY_MASK  CORTEX_PRIORITY_MASK((CORTEX_MAXIMUM_PRIORITY + CORTEX_MINIMUM_PRIORITY) / 2)
+# define UAVCAN_STM32_IRQ_PRIORITY_MASK  CORTEX_PRIORITY_MASK(CORTEX_MAX_KERNEL_PRIORITY)
 #endif
 
 /**