From 572ea07e84b38ea8de0551f4b4eda685d91d09d2 Mon Sep 17 00:00:00 2001
From: Adam Johnson <me@adamj.eu>
Date: Mon, 22 Jan 2024 13:21:13 +0000
Subject: [PATCH] [4.2.x] Fixed CVE-2024-24680 -- Mitigated potential DoS in
 intcomma template filter.

Thanks Seokchan Yoon for the report.

Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>
Co-authored-by: Natalia <124304+nessita@users.noreply.github.com>
Co-authored-by: Shai Berger <shai@platonix.com>
---
 .../contrib/humanize/templatetags/humanize.py | 13 ++--
 tests/humanize_tests/tests.py                 | 64 +++++++++++++++++++
 2 files changed, 71 insertions(+), 6 deletions(-)

diff --git a/django/contrib/humanize/templatetags/humanize.py b/django/contrib/humanize/templatetags/humanize.py
index 2322477..2c26f89 100644
--- a/django/contrib/humanize/templatetags/humanize.py
+++ b/django/contrib/humanize/templatetags/humanize.py
@@ -75,12 +75,13 @@ def intcomma(value, use_l10n=True):
             return intcomma(value, False)
         else:
             return number_format(value, use_l10n=True, force_grouping=True)
-    orig = str(value)
-    new = re.sub(r"^(-?\d+)(\d{3})", r"\g<1>,\g<2>", orig)
-    if orig == new:
-        return new
-    else:
-        return intcomma(new, use_l10n)
+    result = str(value)
+    match = re.match(r"-?\d+", result)
+    if match:
+        prefix = match[0]
+        prefix_with_commas = re.sub(r"\d{3}", r"\g<0>,", prefix[::-1])[::-1]
+        result = prefix_with_commas + result[len(prefix) :]
+    return result
 
 
 # A tuple of standard large number to their converters
diff --git a/tests/humanize_tests/tests.py b/tests/humanize_tests/tests.py
index cf29f58..a78bbad 100644
--- a/tests/humanize_tests/tests.py
+++ b/tests/humanize_tests/tests.py
@@ -116,39 +116,71 @@ class HumanizeTests(SimpleTestCase):
     def test_intcomma(self):
         test_list = (
             100,
+            -100,
             1000,
+            -1000,
             10123,
+            -10123,
             10311,
+            -10311,
             1000000,
+            -1000000,
             1234567.25,
+            -1234567.25,
             "100",
+            "-100",
             "1000",
+            "-1000",
             "10123",
+            "-10123",
             "10311",
+            "-10311",
             "1000000",
+            "-1000000",
             "1234567.1234567",
+            "-1234567.1234567",
             Decimal("1234567.1234567"),
+            Decimal("-1234567.1234567"),
             None,
             "１２３４５６７",
+            "-１２３４５６７",
             "１２３４５６７.１２",
+            "-１２３４５６７.１２",
+            "the quick brown fox jumped over the lazy dog",
         )
         result_list = (
             "100",
+            "-100",
             "1,000",
+            "-1,000",
             "10,123",
+            "-10,123",
             "10,311",
+            "-10,311",
             "1,000,000",
+            "-1,000,000",
             "1,234,567.25",
+            "-1,234,567.25",
             "100",
+            "-100",
             "1,000",
+            "-1,000",
             "10,123",
+            "-10,123",
             "10,311",
+            "-10,311",
             "1,000,000",
+            "-1,000,000",
             "1,234,567.1234567",
+            "-1,234,567.1234567",
             "1,234,567.1234567",
+            "-1,234,567.1234567",
             None,
             "1,234,567",
+            "-1,234,567",
             "１,２３４,５６７.１２",
+            "-１,２３４,５６７.１２",
+            "the quick brown fox jumped over the lazy dog",
         )
         with translation.override("en"):
             self.humanize_tester(test_list, result_list, "intcomma")
@@ -156,39 +188,71 @@ class HumanizeTests(SimpleTestCase):
     def test_l10n_intcomma(self):
         test_list = (
             100,
+            -100,
             1000,
+            -1000,
             10123,
+            -10123,
             10311,
+            -10311,
             1000000,
+            -1000000,
             1234567.25,
+            -1234567.25,
             "100",
+            "-100",
             "1000",
+            "-1000",
             "10123",
+            "-10123",
             "10311",
+            "-10311",
             "1000000",
+            "-1000000",
             "1234567.1234567",
+            "-1234567.1234567",
             Decimal("1234567.1234567"),
+            -Decimal("1234567.1234567"),
             None,
             "１２３４５６７",
+            "-１２３４５６７",
             "１２３４５６７.１２",
+            "-１２３４５６７.１２",
+            "the quick brown fox jumped over the lazy dog",
         )
         result_list = (
             "100",
+            "-100",
             "1,000",
+            "-1,000",
             "10,123",
+            "-10,123",
             "10,311",
+            "-10,311",
             "1,000,000",
+            "-1,000,000",
             "1,234,567.25",
+            "-1,234,567.25",
             "100",
+            "-100",
             "1,000",
+            "-1,000",
             "10,123",
+            "-10,123",
             "10,311",
+            "-10,311",
             "1,000,000",
+            "-1,000,000",
             "1,234,567.1234567",
+            "-1,234,567.1234567",
             "1,234,567.1234567",
+            "-1,234,567.1234567",
             None,
             "1,234,567",
+            "-1,234,567",
             "１,２３４,５６７.１２",
+            "-１,２３４,５６７.１２",
+            "the quick brown fox jumped over the lazy dog",
         )
         with self.settings(USE_THOUSAND_SEPARATOR=False):
             with translation.override("en"):
-- 
2.33.0