diff --git a/src/mdformat/codepoints/__init__.py b/src/mdformat/codepoints/__init__.py
index 37929c1..0559849 100644
--- a/src/mdformat/codepoints/__init__.py
+++ b/src/mdformat/codepoints/__init__.py
@@ -10,7 +10,7 @@
 from mdformat.codepoints._unicode_punctuation import UNICODE_PUNCTUATION
 from mdformat.codepoints._unicode_whitespace import UNICODE_WHITESPACE
 
-ASCII_CTRL = frozenset(chr(i) for i in range(32))
+ASCII_CTRL = frozenset(chr(i) for i in range(32)) | frozenset(chr(127))
 
 
 def __getattr__(name: str) -> frozenset[str]: