diff --git a/resources/chaosknoten/keycloak/docker_compose/compose.yaml.j2 b/resources/chaosknoten/keycloak/docker_compose/compose.yaml.j2
index 9fde708..9bc24fb 100644
--- a/resources/chaosknoten/keycloak/docker_compose/compose.yaml.j2
+++ b/resources/chaosknoten/keycloak/docker_compose/compose.yaml.j2
@@ -46,7 +46,7 @@ services:
       - "8080:8080"
 
   db:
-    image: docker.io/library/postgres:15.14
+    image: docker.io/library/postgres:18.0@sha256:33d0aae6356d4412efdebcdc554e489e7f9e88bb3cf9281f44aa1924fadbb4e7
     restart: unless-stopped
     networks:
       - keycloak
diff --git a/resources/chaosknoten/lists/docker_compose/compose.yaml b/resources/chaosknoten/lists/docker_compose/compose.yaml
index cdfd70a..2af2708 100644
--- a/resources/chaosknoten/lists/docker_compose/compose.yaml
+++ b/resources/chaosknoten/lists/docker_compose/compose.yaml
@@ -56,7 +56,7 @@ services:
       - POSTGRES_DB=mailmandb
       - POSTGRES_USER=mailman
       - POSTGRES_PASSWORD=wvQjbMRnwFuxGEPz
-    image: docker.io/library/postgres:12-alpine
+    image: docker.io/library/postgres:18-alpine@sha256:e08e178a23d51e4a1e9e79fb2500b35b91cef3902744519420d257b8c0fb0a3c
     volumes:
       - /opt/mailman/database:/var/lib/postgresql/data
     networks:
diff --git a/resources/chaosknoten/pad/docker_compose/compose.yaml.j2 b/resources/chaosknoten/pad/docker_compose/compose.yaml.j2
index 455caa3..e492353 100644
--- a/resources/chaosknoten/pad/docker_compose/compose.yaml.j2
+++ b/resources/chaosknoten/pad/docker_compose/compose.yaml.j2
@@ -3,7 +3,7 @@
 
 services:
   database:
-    image: docker.io/library/postgres:15-alpine
+    image: docker.io/library/postgres:18-alpine@sha256:e08e178a23d51e4a1e9e79fb2500b35b91cef3902744519420d257b8c0fb0a3c
     environment:
       - "POSTGRES_USER=hedgedoc"
       - "POSTGRES_PASSWORD={{ secret__hedgedoc_db_password }}"
diff --git a/resources/chaosknoten/pretalx/docker_compose/compose.yaml.j2 b/resources/chaosknoten/pretalx/docker_compose/compose.yaml.j2
index 7b733cb..7ad6c61 100644
--- a/resources/chaosknoten/pretalx/docker_compose/compose.yaml.j2
+++ b/resources/chaosknoten/pretalx/docker_compose/compose.yaml.j2
@@ -3,7 +3,7 @@
 
 services:
   database:
-    image: docker.io/library/postgres:15-alpine
+    image: docker.io/library/postgres:18-alpine@sha256:e08e178a23d51e4a1e9e79fb2500b35b91cef3902744519420d257b8c0fb0a3c
     environment:
       - "POSTGRES_USER=pretalx"
       - "POSTGRES_PASSWORD={{ secret__pretalx_db_password }}"
diff --git a/resources/chaosknoten/tickets/docker_compose/compose.yaml.j2 b/resources/chaosknoten/tickets/docker_compose/compose.yaml.j2
index 6509a99..32491fe 100644
--- a/resources/chaosknoten/tickets/docker_compose/compose.yaml.j2
+++ b/resources/chaosknoten/tickets/docker_compose/compose.yaml.j2
@@ -1,7 +1,7 @@
 ---
 services:
   database:
-    image: docker.io/library/postgres:15-alpine
+    image: docker.io/library/postgres:18-alpine@sha256:e08e178a23d51e4a1e9e79fb2500b35b91cef3902744519420d257b8c0fb0a3c
     environment:
       - "POSTGRES_USER=pretix"
       - "POSTGRES_PASSWORD={{ secret__pretix_db_password }}"