diff --git a/showcase/package-lock.json b/showcase/package-lock.json
index 9dfc1b924f..99c8d450c7 100644
--- a/showcase/package-lock.json
+++ b/showcase/package-lock.json
@@ -4865,9 +4865,9 @@
       "dev": true
     },
     "event-source-polyfill": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/event-source-polyfill/-/event-source-polyfill-1.0.0.tgz",
-      "integrity": "sha512-a5fUuXJS0uuNWsz1t7TKEvbLkraVf4Y6K7tXD+VUncPTmEwadRrZ1cQ6YksfWbazla3uZzvRfcJ8VWu/C30g6g=="
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/event-source-polyfill/-/event-source-polyfill-1.0.3.tgz",
+      "integrity": "sha512-+a+AP1nlLqpbxKwgGuyb7xIqDqpfVrzoz2LzRBeF3X5YhgCocAoCZLpNVDFNv0Y0iGeQsoNWa0kVbZvp/VTp5A=="
     },
     "event-stream": {
       "version": "4.0.1",
diff --git a/showcase/package.json b/showcase/package.json
index 811008cec0..89e32e1514 100644
--- a/showcase/package.json
+++ b/showcase/package.json
@@ -130,7 +130,7 @@
     "basscss": "8.0.10",
     "core-js": "2.5.7",
     "eligrey-classlist-js-polyfill": "1.2.20180112",
-    "event-source-polyfill": "1.0.0",
+    "event-source-polyfill": "1.0.3",
     "http-server": "0.11.1",
     "ngrx-store-freeze": "0.2.4",
     "ngrx-store-logger": "0.2.2",
diff --git a/starter/package-lock.json b/starter/package-lock.json
index c7d5093919..0d44e93dd6 100644
--- a/starter/package-lock.json
+++ b/starter/package-lock.json
@@ -4865,9 +4865,9 @@
       "dev": true
     },
     "event-source-polyfill": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/event-source-polyfill/-/event-source-polyfill-1.0.0.tgz",
-      "integrity": "sha512-a5fUuXJS0uuNWsz1t7TKEvbLkraVf4Y6K7tXD+VUncPTmEwadRrZ1cQ6YksfWbazla3uZzvRfcJ8VWu/C30g6g=="
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/event-source-polyfill/-/event-source-polyfill-1.0.3.tgz",
+      "integrity": "sha512-+a+AP1nlLqpbxKwgGuyb7xIqDqpfVrzoz2LzRBeF3X5YhgCocAoCZLpNVDFNv0Y0iGeQsoNWa0kVbZvp/VTp5A=="
     },
     "event-stream": {
       "version": "4.0.1",
diff --git a/starter/package.json b/starter/package.json
index c06750aa1c..fd301ec3ad 100644
--- a/starter/package.json
+++ b/starter/package.json
@@ -130,7 +130,7 @@
     "basscss": "8.0.10",
     "core-js": "2.5.7",
     "eligrey-classlist-js-polyfill": "1.2.20180112",
-    "event-source-polyfill": "1.0.0",
+    "event-source-polyfill": "1.0.3",
     "http-server": "0.11.1",
     "ngrx-store-freeze": "0.2.4",
     "ngrx-store-logger": "0.2.2",