--- a/src/modules/rlm_python3/configure
+++ b/src/modules/rlm_python3/configure
@@ -2928,15 +2928,15 @@ fi
 
 
 	if test x$fail = x; then
-		PY_PREFIX=`${PYTHON3_BIN} -c 'import sys ; print(sys.prefix)'`
+		PY_PREFIX="$OPENWRTTARGET_PY3_PREFIX"
 		{ $as_echo "$as_me:${as_lineno-$LINENO}: Python sys.prefix \"${PY_PREFIX}\"" >&5
 $as_echo "$as_me: Python sys.prefix \"${PY_PREFIX}\"" >&6;}
 
-		PY_EXEC_PREFIX=`${PYTHON3_BIN} -c 'import sys ; print(sys.exec_prefix)'`
+		PY_EXEC_PREFIX="$OPENWRTTARGET_PY3_PREFIX"
 		{ $as_echo "$as_me:${as_lineno-$LINENO}: Python sys.exec_prefix \"${PY_EXEC_PREFIX}\"" >&5
 $as_echo "$as_me: Python sys.exec_prefix \"${PY_EXEC_PREFIX}\"" >&6;}
 
-		PY_SYS_VERSION=`${PYTHON3_BIN} -c 'import sys ; print(sys.version[0:3])'`
+		PY_SYS_VERSION="$OPENWRTTARGET_PY3_SYS_VERSION"
 		{ $as_echo "$as_me:${as_lineno-$LINENO}: Python sys.version \"${PY_SYS_VERSION}\"" >&5
 $as_echo "$as_me: Python sys.version \"${PY_SYS_VERSION}\"" >&6;}
 
--- a/src/modules/rlm_python3/configure.ac
+++ b/src/modules/rlm_python3/configure.ac
@@ -65,13 +65,13 @@ if test x$with_[]modname != xno; then
 	)
 
 	if test x$fail = x; then
-		PY_PREFIX=`${PYTHON3_BIN} -c 'import sys ; print(sys.prefix)'`
+		PY_PREFIX="$OPENWRTTARGET_PY3_PREFIX"
 		AC_MSG_NOTICE([Python sys.prefix \"${PY_PREFIX}\"])
 
-		PY_EXEC_PREFIX=`${PYTHON3_BIN} -c 'import sys ; print(sys.exec_prefix)'`
+		PY_EXEC_PREFIX="$OPENWRTTARGET_PY3_PREFIX"
 		AC_MSG_NOTICE([Python sys.exec_prefix \"${PY_EXEC_PREFIX}\"])
 
-		PY_SYS_VERSION=`${PYTHON3_BIN} -c 'import sys ; print(sys.version[[0:3]])'`
+		PY_SYS_VERSION="$OPENWRTTARGET_PY3_SYS_VERSION"
 		AC_MSG_NOTICE([Python sys.version \"${PY_SYS_VERSION}\"])
 
 		if test "x$PY_LIB_DIR" = "x"; then