diff --git a/package.json b/package.json
index 05504dc0..cf1bd11d 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "rollup": "^1.2.1",
     "rollup-plugin-typescript": "^1.0.0",
     "rollup-plugin-typescript2": "^0.19.2",
-    "terser": "^3.16.1",
+    "terser": "^4.8.1",
     "ts-jest": "^23.10.5",
     "tslint": "^5.12.1",
     "tslint-config-prettier": "^1.18.0",
diff --git a/yarn.lock b/yarn.lock
index fc03ce46..60a4cabd 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -630,10 +630,10 @@ combined-stream@^1.0.6, combined-stream@~1.0.6:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@^2.12.1:
-  version "2.19.0"
-  resolved "https://registry.yarnpkg.com/commander/-/commander-2.19.0.tgz#f6198aa84e5b83c46054b94ddedbfed5ee9ff12a"
-  integrity sha512-6tvAOO+D6OENvRAh524Dh9jcfKTYDQAqvqezbCW82xj5X0pSrcpxtvRKHLG0yBY6SD7PSDrJaj+0AiOcKVd1Xg==
+commander@^2.12.1, commander@^2.20.0:
+  version "2.20.3"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
+  integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
 
 commander@~2.17.1:
   version "2.17.1"
@@ -3227,10 +3227,10 @@ source-map-resolve@^0.5.0:
     source-map-url "^0.4.0"
     urix "^0.1.0"
 
-source-map-support@^0.5.6, source-map-support@~0.5.9:
-  version "0.5.10"
-  resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.5.10.tgz#2214080bc9d51832511ee2bab96e3c2f9353120c"
-  integrity sha512-YfQ3tQFTK/yzlGJuX8pTwa4tifQj4QS2Mj7UegOu8jAz59MqIiMGPXxQhVQiIMNzayuUSF/jEuVnfFF5JqybmQ==
+source-map-support@^0.5.6, source-map-support@~0.5.12:
+  version "0.5.21"
+  resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.5.21.tgz#04fe7c7f9e1ed2d662233c28cb2b35b9f63f6e4f"
+  integrity sha512-uBHU3L3czsIyYXKX88fdrGovxdSCoTGDRZ6SYXtSRxLZUzHg5P/66Ht6uoUlHu9EZod+inXhKo3qQgwXUT/y1w==
   dependencies:
     buffer-from "^1.0.0"
     source-map "^0.6.0"
@@ -3426,14 +3426,14 @@ tar@^4:
     safe-buffer "^5.1.2"
     yallist "^3.0.2"
 
-terser@^3.16.1:
-  version "3.16.1"
-  resolved "https://registry.yarnpkg.com/terser/-/terser-3.16.1.tgz#5b0dd4fa1ffd0b0b43c2493b2c364fd179160493"
-  integrity sha512-JDJjgleBROeek2iBcSNzOHLKsB/MdDf+E/BOAJ0Tk9r7p9/fVobfv7LMJ/g/k3v9SXdmjZnIlFd5nfn/Rt0Xow==
+terser@^4.8.1:
+  version "4.8.1"
+  resolved "https://registry.yarnpkg.com/terser/-/terser-4.8.1.tgz#a00e5634562de2239fd404c649051bf6fc21144f"
+  integrity sha512-4GnLC0x667eJG0ewJTa6z/yXrbLGv80D9Ru6HIpCQmO+Q4PfEtBFi0ObSckqwL6VyQv/7ENJieXHo2ANmdQwgw==
   dependencies:
-    commander "~2.17.1"
+    commander "^2.20.0"
     source-map "~0.6.1"
-    source-map-support "~0.5.9"
+    source-map-support "~0.5.12"
 
 test-exclude@^5.0.0:
   version "5.1.0"