diff --git a/.github/workflows/core.yml b/.github/workflows/core.yml
index da0de8b2..3c7eaecc 100644
--- a/.github/workflows/core.yml
+++ b/.github/workflows/core.yml
@@ -244,7 +244,7 @@ jobs:
           fi
 
           if [[ $OS =~ ^ubuntu.*$ && ! $TARGET =~ ^.*freebsd$ ]]; then
-            UPX_VERSION=5.0.1
+            UPX_VERSION=4.2.4
             curl -L https://github.com/upx/upx/releases/download/v${UPX_VERSION}/upx-${UPX_VERSION}-amd64_linux.tar.xz -s | tar xJvf -
             cp upx-${UPX_VERSION}-amd64_linux/upx .
             ./upx --lzma --best ./target/$TARGET/release/easytier-core"$SUFFIX"
@@ -316,4 +316,4 @@ jobs:
             ./easytier-contrib/easytier-magisk
             !./easytier-contrib/easytier-magisk/build.sh
             !./easytier-contrib/easytier-magisk/magisk_update.json
-          if-no-files-found: error
\ No newline at end of file
+          if-no-files-found: error