diff --git a/securedrop/source_app/api.py b/securedrop/source_app/api.py
index 53661f6dbf..6667d9ba4a 100644
--- a/securedrop/source_app/api.py
+++ b/securedrop/source_app/api.py
@@ -1,4 +1,5 @@
 import json
+import platform
 
 from flask import Blueprint, make_response
 
@@ -12,6 +13,7 @@ def make_blueprint(config):
     def metadata():
         meta = {'gpg_fpr': config.JOURNALIST_KEY,
                 'sd_version': version.__version__,
+                'server_os': platform.linux_distribution()[1],
                 }
         resp = make_response(json.dumps(meta))
         resp.headers['Content-Type'] = 'application/json'
diff --git a/securedrop/tests/test_source.py b/securedrop/tests/test_source.py
index dd8d9527dd..fac86fff7d 100644
--- a/securedrop/tests/test_source.py
+++ b/securedrop/tests/test_source.py
@@ -16,6 +16,7 @@
 from db import db
 from models import Source, Reply
 from source_app import main as source_app_main
+from source_app import api as source_app_api
 from utils.db_helper import new_codename
 from utils.instrument import InstrumentedApp
 
@@ -516,12 +517,16 @@ def test_why_journalist_key(source_app):
 
 
 def test_metadata_route(source_app):
-    with source_app.test_client() as app:
-        resp = app.get(url_for('api.metadata'))
-        assert resp.status_code == 200
-        assert resp.headers.get('Content-Type') == 'application/json'
-        assert json.loads(resp.data.decode('utf-8')).get('sd_version') \
-            == version.__version__
+    with patch.object(source_app_api.platform, "linux_distribution") as mocked_platform:
+        mocked_platform.return_value = ("Ubuntu", "16.04", "xenial")
+        with source_app.test_client() as app:
+            resp = app.get(url_for('api.metadata'))
+            assert resp.status_code == 200
+            assert resp.headers.get('Content-Type') == 'application/json'
+            assert json.loads(resp.data.decode('utf-8')).get('sd_version') \
+                == version.__version__
+            assert json.loads(resp.data.decode('utf-8')).get('server_os') \
+                == '16.04'
 
 
 def test_login_with_overly_long_codename(source_app):