diff --git a/key.go b/key.go
index 8e88c68..dbb608a 100644
--- a/key.go
+++ b/key.go
@@ -624,6 +624,12 @@ func readInputs(input io.Reader) ([]Msg, error) {
 			continue
 		}
 
+		// Is this an unrecognized CSI sequence? If so, ignore it.
+		if len(runes) > 2 && runes[0] == 0x1b && (runes[1] == '[' ||
+			(len(runes) > 3 && runes[1] == 0x1b && runes[2] == '[')) {
+			continue
+		}
+
 		// Is the alt key pressed? If so, the buffer will be prefixed with an
 		// escape.
 		alt := false
diff --git a/key_test.go b/key_test.go
index 869b32f..a73fed8 100644
--- a/key_test.go
+++ b/key_test.go
@@ -152,6 +152,10 @@ func TestReadInput(t *testing.T) {
 				},
 			},
 		},
+		"unrecognized": {
+			[]byte{'\x1b', '[', '-', '-', '-', '-', 'X'},
+			[]Msg{},
+		},
 	} {
 		t.Run(out, func(t *testing.T) {
 			msgs, err := readInputs(bytes.NewReader(td.in))