diff --git a/listing-12.4/server/package-lock.json b/listing-12.4/server/package-lock.json
index 2425914..d090022 100644
--- a/listing-12.4/server/package-lock.json
+++ b/listing-12.4/server/package-lock.json
@@ -5,25 +5,34 @@
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-      "version": "1.0.9",
-      "resolved": "https://registry.npmjs.org/bson/-/bson-1.0.9.tgz",
-      "integrity": "sha512-IQX9/h7WdMBIW/q/++tGd+emQr0XMdeZ6icnT/74Xk9fnabWn+gZgpE+9V+gujL3hhJOoNrnDVY7tWdzc7NUTg=="
+      "version": "1.1.5",
+      "resolved": "https://registry.npmjs.org/bson/-/bson-1.1.5.tgz",
+      "integrity": "sha512-kDuEzldR21lHciPQAIulLs1LZlCXdLziXI6Mb/TDkwXhb//UORJNPXgcRs2CuO4H0DcMkpfT3/ySsP3unoZjBg=="
+    },
+    "memory-pager": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/memory-pager/-/memory-pager-1.5.0.tgz",
+      "integrity": "sha512-ZS4Bp4r/Zoeq6+NLJpP+0Zzm0pR8whtGPf1XExKLJBAczGMnSi3It14OiNCStjQjM6NU1okjQGSxgEZN8eBYKg==",
+      "optional": true
     },
     "mongodb": {
-      "version": "3.0.5",
-      "resolved": "https://registry.npmjs.org/mongodb/-/mongodb-3.0.5.tgz",
-      "integrity": "sha512-8ioTyyc8tkNwZCTDa1FPWvmpJFfvE484DnugC8KpVrw4AKAE03OOAlORl2yYTNtz3TX4Ab7FRo00vzgexB/67A==",
+      "version": "3.1.13",
+      "resolved": "https://registry.npmjs.org/mongodb/-/mongodb-3.1.13.tgz",
+      "integrity": "sha512-sz2dhvBZQWf3LRNDhbd30KHVzdjZx9IKC0L+kSZ/gzYquCF5zPOgGqRz6sSCqYZtKP2ekB4nfLxhGtzGHnIKxA==",
       "requires": {
-        "mongodb-core": "3.0.5"
+        "mongodb-core": "3.1.11",
+        "safe-buffer": "^5.1.2"
       }
     },
     "mongodb-core": {
-      "version": "3.0.5",
-      "resolved": "https://registry.npmjs.org/mongodb-core/-/mongodb-core-3.0.5.tgz",
-      "integrity": "sha512-4A1nx/xAU5d/NPICjiyzVxzNrIdJQQsYRe3xQkV1O638t+fHHfAOLK+SQagqGnu1m0aeSxb1ixp/P0FGSQWIGA==",
+      "version": "3.1.11",
+      "resolved": "https://registry.npmjs.org/mongodb-core/-/mongodb-core-3.1.11.tgz",
+      "integrity": "sha512-rD2US2s5qk/ckbiiGFHeu+yKYDXdJ1G87F6CG3YdaZpzdOm5zpoAZd/EKbPmFO6cQZ+XVXBXBJ660sSI0gc6qg==",
       "requires": {
-        "bson": "1.0.9",
-        "require_optional": "1.0.1"
+        "bson": "^1.1.0",
+        "require_optional": "^1.0.1",
+        "safe-buffer": "^5.1.2",
+        "saslprep": "^1.0.0"
       }
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     "require_optional": {
@@ -31,8 +40,8 @@
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       "integrity": "sha512-qhM/y57enGWHAe3v/NcwML6a3/vfESLe/sGM2dII+gEO0BpKRUkWZow/tyloNqJyN6kXSl3RyyM8Ll5D/sJP8g==",
       "requires": {
-        "resolve-from": "2.0.0",
-        "semver": "5.5.0"
+        "resolve-from": "^2.0.0",
+        "semver": "^5.1.0"
       }
     },
     "resolve-from": {
@@ -40,10 +49,33 @@
       "resolved": "https://registry.npmjs.org/resolve-from/-/resolve-from-2.0.0.tgz",
       "integrity": "sha1-lICrIOlP+h2egKgEx+oUdhGWa1c="
     },
+    "safe-buffer": {
+      "version": "5.2.1",
+      "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.2.1.tgz",
+      "integrity": "sha512-rp3So07KcdmmKbGvgaNxQSJr7bGVSVk5S9Eq1F+ppbRo70+YeaDxkw5Dd8NPN+GD6bjnYm2VuPuCXmpuYvmCXQ=="
+    },
+    "saslprep": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/saslprep/-/saslprep-1.0.3.tgz",
+      "integrity": "sha512-/MY/PEMbk2SuY5sScONwhUDsV2p77Znkb/q3nSVstq/yQzYJOH/Azh29p9oJLsl3LnQwSvZDKagDGBsBwSooag==",
+      "optional": true,
+      "requires": {
+        "sparse-bitfield": "^3.0.3"
+      }
+    },
     "semver": {
-      "version": "5.5.0",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-5.5.0.tgz",
-      "integrity": "sha512-4SJ3dm0WAwWy/NVeioZh5AntkdJoWKxHxcmyP622fOkgHa4z3R0TdBJICINyaSDE6uNwVc8gZr+ZinwZAH4xIA=="
+      "version": "5.7.1",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
+      "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ=="
+    },
+    "sparse-bitfield": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/sparse-bitfield/-/sparse-bitfield-3.0.3.tgz",
+      "integrity": "sha1-/0rm5oZWBWuks+eSqzM004JzyhE=",
+      "optional": true,
+      "requires": {
+        "memory-pager": "^1.0.2"
+      }
     }
   }
 }
diff --git a/listing-12.4/server/package.json b/listing-12.4/server/package.json
index 043e4d0..3abeca5 100644
--- a/listing-12.4/server/package.json
+++ b/listing-12.4/server/package.json
@@ -10,6 +10,6 @@
   "author": "",
   "license": "MIT",
   "dependencies": {
-    "mongodb": "3.0.5"
+    "mongodb": "3.1.13"
   }
 }