diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 22a19f3..970fa9a 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -52,27 +52,19 @@ jobs:
       - name: Python 3 integration tests
         run: PYTHONPATH=. python3 ./tests/integration_tests.py
 
-  centos-7:
-    name: CentOS 7
+  fedora-40:
+    name: Fedora 40
     runs-on: ubuntu-latest
-    container: centos:7
+    container: fedora:40
     steps:
-      - run: yum -y install epel-release
       - run: |
-          yum -y install \
-            python2-pytest \
-            python2-pyyaml \
-            python36-pytest \
-            python36-yaml
-      - uses: actions/checkout@v1
-
-      - name: Python 2 unit tests
-        run: PYTHONPATH=. py.test-2.7
-      - name: Python 2 integration tests
-        run: PYTHONPATH=. python2 ./tests/integration_tests.py
-
+          dnf -y install \
+            python3 \
+            python3-pytest \
+            python3-pyyaml
+      - uses: actions/checkout@v4
       - name: Python 3 unit tests
-        run: PYTHONPATH=. py.test-3
+        run: PYTHONPATH=. pytest-3
       - name: Python 3 integration tests
         run: PYTHONPATH=. python3 ./tests/integration_tests.py
 
@@ -92,17 +84,17 @@ jobs:
       - name: Python 3 integration tests
         run: PYTHONPATH=. python3 ./tests/integration_tests.py
 
-  fedora-38:
-    name: Fedora 38
+  ubuntu-2404:
+    name: Ubuntu 24.04
     runs-on: ubuntu-latest
-    container: fedora:38
+    container: ubuntu:24.04
     steps:
+      - run: apt update
       - run: |
-          dnf -y install \
-            python3 \
+          apt -y install \
             python3-pytest \
-            python3-pyyaml
-      - uses: actions/checkout@v2
+            python3-yaml
+      - uses: actions/checkout@v1
       - name: Python 3 unit tests
         run: PYTHONPATH=. pytest-3
       - name: Python 3 integration tests
@@ -234,9 +226,10 @@ jobs:
     name: MacOS Latest
     runs-on: macos-latest
     steps:
+      - run: PATH="/usr/local/opt/python/libexec/bin:$PATH" >> $GITHUB_ENV
       - run: brew install python
-      - run: pip3 install PyYAML
-      - run: pip3 install pytest
+      - run: brew install PyYAML
+      - run: pip3 install --break-system-packages pytest
       - uses: actions/checkout@v1
       - run: PYTHONPATH=. python3 -m pytest
       - run: PYTHONPATH=. python3 ./tests/integration_tests.py
diff --git a/suricata/update/main.py b/suricata/update/main.py
index 7814518..099d591 100644
--- a/suricata/update/main.py
+++ b/suricata/update/main.py
@@ -114,8 +114,7 @@ def check_checksum(self, tmp_filename, url, checksum_url=None):
             if not isinstance(checksum_url, str):
                 checksum_url = url[0] + ".md5"
             net_arg=(checksum_url,url[1])
-            local_checksum = hashlib.md5(
-                open(tmp_filename, "rb").read()).hexdigest().strip()
+            local_checksum = util.md5_hexdigest(open(tmp_filename, "rb").read())
             remote_checksum_buf = io.BytesIO()
             logger.info("Checking %s." % (checksum_url))
             net.get(net_arg, remote_checksum_buf)
@@ -154,7 +153,7 @@ def url_basename(self, url):
         return filename
 
     def get_tmp_filename(self, url):
-        url_hash = hashlib.md5(url.encode("utf-8")).hexdigest()
+        url_hash = util.md5_hexdigest(url.encode("utf-8"))
         return os.path.join(
             config.get_cache_dir(),
             "%s-%s" % (url_hash, self.url_basename(url)))
@@ -470,7 +469,7 @@ def handle_dataset_files(rule, dep_files):
             return
         dataset_contents = dep_files[source_filename]
 
-    source_filename_hash = hashlib.md5(source_filename.encode()).hexdigest()
+    source_filename_hash = util.md5_hexdigest(source_filename.encode())
     new_rule = re.sub(r"(dataset.*?load\s+){}".format(dataset_filename), r"\g<1>datasets/{}".format(source_filename_hash), rule.format())
     dest_filename = os.path.join(config.get_output_dir(), "datasets", source_filename_hash)
     dest_dir = os.path.dirname(dest_filename)
@@ -783,7 +782,7 @@ def md5(self, filename):
         if not os.path.exists(filename):
             return ""
         else:
-            return hashlib.md5(open(filename, "rb").read()).hexdigest()
+            return util.md5_hexdigest(open(filename, "rb").read())
 
     def any_modified(self):
         for filename in self.hashes:
@@ -1000,7 +999,7 @@ def load_sources(suricata_version):
     for url in urls:
 
         # To de-duplicate filenames, add a prefix that is a hash of the URL.
-        prefix = hashlib.md5(url[0].encode()).hexdigest()
+        prefix = util.md5_hexdigest(url[0].encode())
         source_files = Fetch().run(url)
         for key in source_files:
             content = source_files[key]
diff --git a/suricata/update/util.py b/suricata/update/util.py
index 50788d8..c2a73d0 100644
--- a/suricata/update/util.py
+++ b/suricata/update/util.py
@@ -22,15 +22,18 @@
 import atexit
 import shutil
 import zipfile
+import sys
 
-def md5_hexdigest(filename):
-    """ Compute the MD5 checksum for the contents of the provided filename.
 
-    :param filename: Filename to computer MD5 checksum of.
+def md5_hexdigest(buf):
+    """ Compute the MD5 checksum for the provided buffer.
 
     :returns: A string representing the hex value of the computed MD5.
     """
-    return hashlib.md5(open(filename).read().encode()).hexdigest()
+    if sys.version_info.major < 3 or (sys.version_info.major == 3 and sys.version_info.minor < 9):
+        return hashlib.md5(buf).hexdigest().strip()
+    else:
+        return hashlib.md5(buf, usedforsecurity=False).hexdigest().strip()
 
 def mktempdir(delete_on_exit=True):
     """ Create a temporary directory that is removed on exit. """
diff --git a/tests/test_util.py b/tests/test_util.py
index 8862f47..ed13c81 100644
--- a/tests/test_util.py
+++ b/tests/test_util.py
@@ -30,4 +30,4 @@ def test_hexdigest(self):
         test_file.flush()
         self.assertEqual(
             "120ea8a25e5d487bf68b5f7096440019",
-            util.md5_hexdigest(test_file.name))
+            util.md5_hexdigest(open(test_file.name).read().encode()))