From 5fd7c868791b635ef20d2991cc028516b9021dd4 Mon Sep 17 00:00:00 2001
From: Sarah Boyce <42296566+sarahboyce@users.noreply.github.com>
Date: Tue, 25 Feb 2025 09:40:54 +0100
Subject: [PATCH] [5.0.x] Fixed CVE-2025-26699 -- Mitigated potential DoS in
 wordwrap template filter.

Thanks sw0rd1ight for the report.

Backport of 55d89e25f4115c5674cdd9b9bcba2bb2bb6d820b from main.

CVE: CVE-2025-26699
Upstream-Status: Backport [https://github.com/django/django/commit/e88f7376fe68]

Backport Changes:
- The fix has been adapted from the upstream Django v4.2.20 patch for
  CVE-2025-26699, applied to the python3-django_5.0.11.bb recipe.

- The upstream patch includes changes to a 4.2.20.txt release-note file.
  This file does not exist in the Django 5.0.11 source tree, so it was
  intentionally omitted from this backport.

- Only the relevant code changes from the upstream patch were applied.
  No functional differences exist in the vulnerable logic between
  Django 4.2.x and 5.0.x.

(cherry picked from commit e88f7376fe68dbf4ebaf11fad1513ce700b45860)
Signed-off-by: Anil Dongare <adongare@cisco.com>
---
 django/utils/text.py                          | 28 +++++++------------
 .../filter_tests/test_wordwrap.py             | 11 ++++++++
 2 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/django/utils/text.py b/django/utils/text.py
index d992f80dd2..36ab6a9efc 100644
--- a/django/utils/text.py
+++ b/django/utils/text.py
@@ -1,6 +1,7 @@
 import gzip
 import re
 import secrets
+import textwrap
 import unicodedata
 from gzip import GzipFile
 from gzip import compress as gzip_compress
@@ -97,24 +98,15 @@ def wrap(text, width):
     ``width``.
     """
 
-    def _generator():
-        for line in text.splitlines(True):  # True keeps trailing linebreaks
-            max_width = min((line.endswith("\n") and width + 1 or width), width)
-            while len(line) > max_width:
-                space = line[: max_width + 1].rfind(" ") + 1
-                if space == 0:
-                    space = line.find(" ") + 1
-                    if space == 0:
-                        yield line
-                        line = ""
-                        break
-                yield "%s\n" % line[: space - 1]
-                line = line[space:]
-                max_width = min((line.endswith("\n") and width + 1 or width), width)
-            if line:
-                yield line
-
-    return "".join(_generator())
+    wrapper = textwrap.TextWrapper(
+        width=width,
+        break_long_words=False,
+        break_on_hyphens=False,
+    )
+    result = []
+    for line in text.splitlines(True):
+        result.extend(wrapper.wrap(line))
+    return "\n".join(result)
 
 
 def add_truncation_text(text, truncate=None):
diff --git a/tests/template_tests/filter_tests/test_wordwrap.py b/tests/template_tests/filter_tests/test_wordwrap.py
index 88fbd274da..4afa1dd234 100644
--- a/tests/template_tests/filter_tests/test_wordwrap.py
+++ b/tests/template_tests/filter_tests/test_wordwrap.py
@@ -78,3 +78,14 @@ class FunctionTests(SimpleTestCase):
             "this is a long\nparagraph of\ntext that\nreally needs\nto be wrapped\n"
             "I'm afraid",
         )
+
+    def test_wrap_long_text(self):
+        long_text = (
+            "this is a long paragraph of text that really needs"
+            " to be wrapped I'm afraid " * 20_000
+        )
+        self.assertIn(
+            "this is a\nlong\nparagraph\nof text\nthat\nreally\nneeds to\nbe wrapped\n"
+            "I'm afraid",
+            wordwrap(long_text, 10),
+        )
-- 
2.43.5