diff --git a/docker/test/fasttest/Dockerfile b/docker/test/fasttest/Dockerfile
index 65ec078d3ca..3cfa57bd747 100644
--- a/docker/test/fasttest/Dockerfile
+++ b/docker/test/fasttest/Dockerfile
@@ -11,7 +11,7 @@ RUN apt-get update \
     && echo "${LLVM_PUBKEY_HASH} /tmp/llvm-snapshot.gpg.key" | sha384sum -c \
     && apt-key add /tmp/llvm-snapshot.gpg.key \
     && export CODENAME="$(lsb_release --codename --short | tr 'A-Z' 'a-z')" \
-    && echo "deb [trusted=yes] http://apt.llvm.org/${CODENAME}/ llvm-toolchain-${CODENAME}-${LLVM_VERSION} main" >> \
+    && echo "deb [trusted=yes] https://apt.llvm.org/${CODENAME}/ llvm-toolchain-${CODENAME}-${LLVM_VERSION} main" >> \
         /etc/apt/sources.list
 
 # initial packages