diff --git a/session-20170418/package.json b/session-20170418/package.json
index 486a458..eb55882 100644
--- a/session-20170418/package.json
+++ b/session-20170418/package.json
@@ -5,7 +5,7 @@
   "license": "MIT",
   "dependencies": {
     "@types/lodash": "^4.14.62",
-    "lodash": "^4.17.13"
+    "lodash": "^4.17.19"
   },
   "devDependencies": {
     "@types/chai": "^3.5.0",
diff --git a/session-20170418/yarn.lock b/session-20170418/yarn.lock
index da3dd8f..11c7d0e 100644
--- a/session-20170418/yarn.lock
+++ b/session-20170418/yarn.lock
@@ -192,9 +192,9 @@ lodash.keys@^3.0.0:
     lodash.isarguments "^3.0.0"
     lodash.isarray "^3.0.0"
 
-lodash@^4.17.13:
-  version "4.17.13"
-  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.13.tgz#0bdc3a6adc873d2f4e0c4bac285df91b64fc7b93"
+lodash@^4.17.19:
+  version "4.17.19"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.19.tgz#e48ddedbe30b3321783c5b4301fbd353bc1e4a4b"
 
 make-error@^1.1.1:
   version "1.2.3"