diff --git a/book/package-lock.json b/book/package-lock.json
index 39d2fd8..ade8439 100644
--- a/book/package-lock.json
+++ b/book/package-lock.json
@@ -206,9 +206,9 @@
       "integrity": "sha1-D6LGT5MpF8NDOg3tVTY6rjdBa3w="
     },
     "lodash": {
-      "version": "4.17.15",
-      "resolved": "https://registry.npm.taobao.org/lodash/download/lodash-4.17.15.tgz",
-      "integrity": "sha1-tEf2ZwoEVbv+7dETku/zMOoJdUg="
+      "version": "4.17.21",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
     },
     "lodash.assignin": {
       "version": "4.2.0",