diff --git a/Dockerfile b/Dockerfile
index aac2a1e..c3b53b4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -5,7 +5,7 @@ ENV SERVICE_PATH deobs.DeobfuScripter
 
 # Install python dependencies
 COPY requirements.txt requirements.txt
-RUN pip install --no-cache-dir --user --requirement requirements.txt && rm -rf ~/.cache/pip
+RUN pip install --no-cache-dir --upgrade --user --requirement requirements.txt && rm -rf ~/.cache/pip
 
 # Copy Crowbar service code
 WORKDIR /opt/al_service
diff --git a/requirements.txt b/requirements.txt
index dfb6339..dd362ad 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,5 +3,5 @@ lxml
 regex
 # assemblyline-service-utilities also depends on multidecoder and pins the version number.
 # Make sure the version ranges are compatible when upgrading.
+multidecoder>=1.3.1,<2.0
 assemblyline-service-utilities>=4.5,<4.6
-multidecoder>=1.2,<2.0