diff --git a/ROMFS/px4fmu_common/init.d-posix/rcS b/ROMFS/px4fmu_common/init.d-posix/rcS
index dbd837d40b..59c33bb396 100644
--- a/ROMFS/px4fmu_common/init.d-posix/rcS
+++ b/ROMFS/px4fmu_common/init.d-posix/rcS
@@ -126,6 +126,15 @@ then
 	set AUTOCNF yes
 fi
 
+# Allow overriding parameters via env variables: export PX4_PARAM_{name}={value}
+env | while IFS='=' read -r line; do
+  value=${line#*=}
+  name=${line%%=*}
+  case $name in
+    "PX4_PARAM_"*) param set "${name#PX4_PARAM_}" "$value" ;;
+  esac
+done
+
 # multi-instance setup
 # shellcheck disable=SC2154
 param set MAV_SYS_ID $((px4_instance+1))
@@ -186,11 +195,6 @@ param set-default SYS_FAILURE_EN 1
 # does not go below 50% by default, but failure injection can trigger failsafes.
 param set-default COM_LOW_BAT_ACT 2
 
-# Allow to override SYS_MC_EST_GROUP via env
-if [ -n "$SYS_MC_EST_GROUP" ]; then
-	param set SYS_MC_EST_GROUP $SYS_MC_EST_GROUP
-fi
-
 # Adapt timeout parameters if simulation runs faster or slower than realtime.
 if [ -n "$PX4_SIM_SPEED_FACTOR" ]; then
 	COM_DL_LOSS_T_LONGER=$(echo "$PX4_SIM_SPEED_FACTOR * 10" | bc)
diff --git a/test/mavsdk_tests/configs/sitl.json b/test/mavsdk_tests/configs/sitl.json
index f2bf6e74b1..7a30054b41 100644
--- a/test/mavsdk_tests/configs/sitl.json
+++ b/test/mavsdk_tests/configs/sitl.json
@@ -16,7 +16,7 @@
             "test_filter": "[offboard_attitude]",
             "timeout_min": 10,
             "env": {
-                "SYS_MC_EST_GROUP": 3
+                "PX4_PARAM_SYS_MC_EST_GROUP": 3
             }
         },
         {