diff --git a/common/Kconfig.boot b/common/Kconfig.boot
index f9551b206f5d0db6abffaf5315691381e5c0e3e9..e0cca226da4fbb59012f14c76e03ae1ed447799b 100644
--- a/common/Kconfig.boot
+++ b/common/Kconfig.boot
@@ -791,6 +791,15 @@ config AUTOBOOT_KEYED
 	  U-Boot automatic booting process and bring the device
 	  to the U-Boot prompt for user input.
 
+config AUTOBOOT_FLUSH_STDIN
+	bool "Enable flushing stdin before starting to read the password"
+	depends on AUTOBOOT_KEYED && !SANDBOX
+	help
+	  When this option is enabled stdin buffer will be flushed before
+	  starting to read the password.
+	  This can't be enabled for the sandbox as flushing stdin would
+	  break the autoboot unit tests.
+
 config AUTOBOOT_PROMPT
 	string "Autoboot stop prompt"
 	depends on AUTOBOOT_KEYED
diff --git a/common/autoboot.c b/common/autoboot.c
index 2564ef8a561d7de65447c9579fd41fff8d29a400..35ef526c42f17e7d6f328a88be9621d33eb8aaa7 100644
--- a/common/autoboot.c
+++ b/common/autoboot.c
@@ -297,6 +297,15 @@ static int passwd_abort_key(uint64_t etime)
 	return abort;
 }
 
+/**
+ * flush_stdin() - drops all pending characters from stdin
+ */
+static void flush_stdin(void)
+{
+	while (tstc())
+		(void)getchar();
+}
+
 /***************************************************************************
  * Watch for 'delay' seconds for autoboot stop or autoboot delay string.
  * returns: 0 -  no key string, allow autoboot 1 - got key string, abort
@@ -306,6 +315,8 @@ static int abortboot_key_sequence(int bootdelay)
 	int abort;
 	uint64_t etime = endtick(bootdelay);
 
+	if (IS_ENABLED(CONFIG_AUTOBOOT_FLUSH_STDIN))
+		flush_stdin();
 #  ifdef CONFIG_AUTOBOOT_PROMPT
 	/*
 	 * CONFIG_AUTOBOOT_PROMPT includes the %d for all boards.