Fixed issue where IDNA 2008 encoded domains were not validated

django/core/validators.py

@@ -6,7 +6,7 @@ from urllib.parse import urlsplit
 
 from django.core.exceptions import ValidationError
 from django.utils.deconstruct import deconstructible
-from django.utils.encoding import punycode
+from django.utils.encoding import idna2008_encode
 from django.utils.ipv6 import is_valid_ipv6_address
 from django.utils.regex_helper import _lazy_re_compile
 from django.utils.translation import gettext_lazy as _
@@ -254,7 +254,8 @@ class EmailValidator:
         ):
             # Try for possible IDN domain-part
             try:
-                domain_part = punycode(domain_part)
+                domain_part = idna2008_encode(domain_part)
+                
             except UnicodeError:
                 pass
             else:
@@ -679,4 +680,4 @@ class ProhibitNullCharactersValidator:
             isinstance(other, self.__class__)
             and self.message == other.message
             and self.code == other.code
-        )
+        )

django/utils/encoding.py

@@ -4,7 +4,7 @@ import locale
 from decimal import Decimal
 from types import NoneType
 from urllib.parse import quote
-
+import unicodedata
 from django.utils.functional import Promise
 
 
@@ -209,6 +209,22 @@ def punycode(domain):
     """Return the Punycode of the given domain if it's non-ASCII."""
     return domain.encode("idna").decode("ascii")
 
+def idna2008_encode(domain):
+    """
+    Encode a domain name according to IDNA 2008 (simplified version).
+    """
+    def encode_label(label):
+        if all(ord(c) < 128 for c in label):
+            # Label contains only ASCII characters
+            return label
+        # Normalize and encode to Punycode
+        normalized_label = unicodedata.normalize('NFC', label)
+        return f"xn--{normalized_label.encode('punycode').decode('ascii')}"
+    
+    labels = domain.split(".")
+    ascii_labels = [encode_label(label) for label in labels]
+    return ".".join(ascii_labels)
+
 
 def repercent_broken_unicode(path):
     """

tests/validators/tests.py

@@ -319,6 +319,22 @@ TEST_DATA = [
     (validate_email, "example@inv-.alid-.com", ValidationError),
     (validate_email, "example@inv-.-alid.com", ValidationError),
     (validate_email, 'test@example.com\n\n<script src="x.js">', ValidationError),
+    (validate_email, 'email@domain.com', None),
+    (validate_email, 'email@xn--4ca9at.com', None),
+    (validate_email, 'email@öäü.com', None),
+    (validate_email, 'email@עִתוֹן.example.il', None),
+    (validate_email, 'email@މިހާރު.example.mv', None),
+    (validate_email, 'email@漢字.example.com', None),
+    (validate_email, "editor@މިހާރު.example.mv", None),
+    (validate_email, 'email@', ValidationError),
+    (validate_email, '@domain.com', ValidationError),
+    (validate_email, 'email.domain.com', ValidationError),
+    (validate_email, 'email@domain@domain.com', ValidationError),
+    (validate_email, 'email@domain..com', ValidationError),
+    (validate_email, 'email@.domain.com', ValidationError),
+    (validate_email, 'email@-domain.com', ValidationError),
+    (validate_email, 'email@domain-.com', ValidationError),
+    (validate_email, 'email@domain.com-', ValidationError),
     # Quoted-string format (CR not allowed)
     (validate_email, '"\\\011"@here.com', None),
     (validate_email, '"\\\012"@here.com', ValidationError),