diff --git a/lib/performance/SizeLimitsPlugin.js b/lib/performance/SizeLimitsPlugin.js
index 5da62ab8a19..24a87fa5e09 100644
--- a/lib/performance/SizeLimitsPlugin.js
+++ b/lib/performance/SizeLimitsPlugin.js
@@ -40,6 +40,7 @@ module.exports = class SizeLimitsPlugin {
 				entrypoint.getFiles().reduce((currentSize, file) => {
 					const asset = compilation.getAsset(file);
 					if (
+						asset &&
 						assetFilter(asset.name, asset.source, asset.info) &&
 						asset.source
 					) {