diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4e018879..de86333d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,16 @@
+# 2020-05-19
+
+## (Compatibility Break / Security Issue) Disabling User Directory search powered by the ma1sd Identity Server
+
+User Directory search requests used to go to the ma1sd identity server by default, which queried its own stores and the Synapse database.
+
+ma1sd current has [a security issue](https://github.com/ma1uta/ma1sd/issues/44), which made it leak information about all users - including users created by bridges, etc.
+
+Until the issue gets fixed, we're making User Directory search not go to ma1sd by default. You **need to re-run the playbook and restart services to apply this workaround**.
+
+*If you insist on restoring the old behavior* (**which has a security issue!**), you *might* use this configuration: `matrix_nginx_proxy_proxy_matrix_user_directory_search_enabled: "{{ matrix_ma1sd_enabled }}"`
+
+
 # 2020-04-28
 
 ## Newer IRC bridge (with potential breaking change)
@@ -11,6 +24,7 @@ If you did not include `mappings` in your configuration for IRC, no
 change is necessary.  `mappings` is not part of the default
 configuration.
 
+
 # 2020-04-23
 
 ## Slack bridging support
diff --git a/group_vars/matrix_servers b/group_vars/matrix_servers
index 970a5703..6d9876ac 100755
--- a/group_vars/matrix_servers
+++ b/group_vars/matrix_servers
@@ -616,7 +616,10 @@ matrix_nginx_proxy_proxy_synapse_metrics: "{{ matrix_synapse_metrics_enabled }}"
 matrix_nginx_proxy_proxy_synapse_metrics_addr_with_container: "matrix-synapse:{{ matrix_synapse_metrics_port }}"
 matrix_nginx_proxy_proxy_synapse_metrics_addr_sans_container: "127.0.0.1:{{ matrix_synapse_metrics_port }}"
 
-matrix_nginx_proxy_proxy_matrix_user_directory_search_enabled: "{{ matrix_ma1sd_enabled }}"
+# Not proxying the user directory search to the identity server by default anymore,
+# because it currently leaks data.
+# See: https://github.com/ma1uta/ma1sd/issues/44
+matrix_nginx_proxy_proxy_matrix_user_directory_search_enabled: false
 matrix_nginx_proxy_proxy_matrix_user_directory_search_addr_with_container: "{{ matrix_nginx_proxy_proxy_matrix_identity_api_addr_with_container }}"
 matrix_nginx_proxy_proxy_matrix_user_directory_search_addr_sans_container: "{{ matrix_nginx_proxy_proxy_matrix_identity_api_addr_sans_container }}"