diff --git a/Dockerfile b/Dockerfile
index 36c488f..413da58 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,6 @@
-FROM docker.io/alpine:3.17 AS builder
+FROM docker.io/alpine:3.18 AS builder
 
-ENV VERSION=v1.84.1
+ENV VERSION=v1.85.2
 
 RUN apk add --no-cache \
   alpine-sdk \
@@ -15,7 +15,7 @@ RUN apk add --no-cache \
 
 RUN pip3 install --target="/install" matrix-synapse==$VERSION
 
-FROM docker.io/thallian/confd-env:3.17-3.1.3.0
+FROM docker.io/thallian/confd-env:3.18-3.1.5.0
 
 RUN addgroup -g 2222 matrix-synapse
 RUN adduser -h /var/lib/matrix-synapse -u 2222 -D -G matrix-synapse matrix-synapse