diff --git a/package.json b/package.json
index 635cb1e..b396d8a 100644
--- a/package.json
+++ b/package.json
@@ -10,7 +10,7 @@
   "license": "ISC",
   "dependencies": {
     "fastpriorityqueue": "^0.2.4",
-    "lodash": "^4.17.19"
+    "lodash": "^4.17.21"
   },
   "devDependencies": {
     "babel-jest": "^19.0.0",
diff --git a/yarn.lock b/yarn.lock
index 054c660..86a6c68 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1988,10 +1988,10 @@ locate-path@^2.0.0:
     p-locate "^2.0.0"
     path-exists "^3.0.0"
 
-lodash@^4.17.14, lodash@^4.17.19, lodash@^4.17.4:
-  version "4.17.19"
-  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.19.tgz#e48ddedbe30b3321783c5b4301fbd353bc1e4a4b"
-  integrity sha512-JNvd8XER9GQX0v2qJgsaN/mzFCNA5BRe/j8JN9d+tWyGLSodKQHKFicdwNYzWwI3wjRnaKPsGj1XkBjx/F96DQ==
+lodash@^4.17.14, lodash@^4.17.21, lodash@^4.17.4:
+  version "4.17.21"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.21.tgz#679591c564c3bffaae8454cf0b3df370c3d6911c"
+  integrity sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==
 
 loose-envify@^1.0.0:
   version "1.4.0"