diff --git a/.gitea/workflows/release.yaml b/.gitea/workflows/release.yaml
index fca27e7..c35d805 100644
--- a/.gitea/workflows/release.yaml
+++ b/.gitea/workflows/release.yaml
@@ -8,7 +8,7 @@ jobs:
   build:
     name: Build image
     runs-on: ubuntu-latest
-    container: ghcr.io/catthehacker/ubuntu:act-latest
+    container: ghcr.io/catthehacker/ubuntu:act-latest@sha256:91f67c0ca67fde4eceb59cb8c3c74cde09c074eadaf9ebc0050df11cd031ef21
     env:
       IMAGE_NAME: mlflow
       REGISTRY: git.namesny.com
diff --git a/Dockerfile b/Dockerfile
index 17db27a..f426c5e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3.10-slim
+FROM python:3.10-slim@sha256:25f03d17398b3f001e040fc951b4ee9404862f1b65c5eea1aa31c042dfdab527
 COPY requirements.txt .
 RUN pip install -r requirements.txt
 EXPOSE 5000