diff --git a/.gitea/workflows/sonarqube.yml b/.gitea/workflows/sonarqube.yml
index e4ce1e95..1ab8b372 100644
--- a/.gitea/workflows/sonarqube.yml
+++ b/.gitea/workflows/sonarqube.yml
@@ -72,6 +72,10 @@ jobs:
 
       - name: SonarQube Analysis
         run: |
+          # Derive JAVA_HOME from the java binary on PATH (set by build image)
+          if [ -z "$JAVA_HOME" ]; then
+            export JAVA_HOME=$(dirname $(dirname $(readlink -f $(which java))))
+          fi
           sonar-scanner \
             -Dsonar.host.url="$SONAR_HOST_URL" \
             -Dsonar.token="$SONAR_TOKEN" \