Issue #22028: Ensure mimetypes will not open registry keys with embedded nulls

diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index ec8fd995ee97511a3e77ba968dfd6ce4ede21a5d..a39b543c4c9ac08dc2eedc039bf0415ebc18f40f 100644 (file)
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -242,9 +242,12 @@ class MimeTypes:
             i = 0
             while True:
                 try:
-                    yield _winreg.EnumKey(mimedb, i)
+                    ctype = _winreg.EnumKey(mimedb, i)
                 except EnvironmentError:
                     break
+                else:
+                    if '\0' not in ctype:
+                        yield ctype
                 i += 1
 
         default_encoding = sys.getdefaultencoding()