diff --git a/package.json b/package.json
index 78f49ee..b94e687 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "gatsby-transformer-remark": "x",
     "gatsby-transformer-sharp": "x",
     "lodash": "^4.17.13",
-    "prismjs": "^1.15.0",
+    "prismjs": "^1.21.0",
     "react": "^16.3.2",
     "react-dom": "^16.3.2",
     "react-helmet": "^5.2.0",
diff --git a/yarn.lock b/yarn.lock
index 12adddc..c263d14 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -9921,10 +9921,10 @@ pretty-error@^2.1.1:
     renderkid "^2.0.1"
     utila "~0.4"
 
-prismjs@^1.15.0:
-  version "1.19.0"
-  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.19.0.tgz#713afbd45c3baca4b321569f2df39e17e729d4dc"
-  integrity sha512-IVFtbW9mCWm9eOIaEkNyo2Vl4NnEifis2GQ7/MLRG5TQe6t+4Sj9J5QWI9i3v+SS43uZBlCAOn+zYTVYQcPXJw==
+prismjs@^1.21.0:
+  version "1.21.0"
+  resolved "https://registry.yarnpkg.com/prismjs/-/prismjs-1.21.0.tgz#36c086ec36b45319ec4218ee164c110f9fc015a3"
+  integrity sha512-uGdSIu1nk3kej2iZsLyDoJ7e9bnPzIgY0naW/HdknGj61zScaprVEVGHrPoXqI+M9sP0NDnTK2jpkvmldpuqDw==
   optionalDependencies:
     clipboard "^2.0.0"