diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7a816a9..dca6405 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,7 +8,7 @@ on:
 jobs:
   validation:
     name: "CS, PHPStan, Security"
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
     strategy:
       fail-fast: false
       matrix: