diff --git a/openthread_border_router/CHANGELOG.md b/openthread_border_router/CHANGELOG.md
index a01692f48..4c5090a1c 100644
--- a/openthread_border_router/CHANGELOG.md
+++ b/openthread_border_router/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## 3.1.2
+
+- Fix upstream DNS/DNS64 resolution for Thread devices by not binding the upstream DNS resolver socket to the infra interface (fixes #3947, regression since 2.12.0)
+
 ## 3.1.1
 
 - Bump beta to OTBR POSIX version d83ddc62 to test ePSKc / Thread 1.4 Credentials Sharing support ahead of the upstream `release-v2026.09.0` tag
diff --git a/openthread_border_router/config.yaml b/openthread_border_router/config.yaml
index cf5038cdf..3bf4813e9 100644
--- a/openthread_border_router/config.yaml
+++ b/openthread_border_router/config.yaml
@@ -1,5 +1,5 @@
 ---
-version: 3.1.1
+version: 3.1.2
 breaking_versions: [3.0.0]
 slug: openthread_border_router
 name: OpenThread Border Router
diff --git a/openthread_border_router/openthread-core-ha-config-posix.h b/openthread_border_router/openthread-core-ha-config-posix.h
index 699e31aea..2fd96b1f8 100644
--- a/openthread_border_router/openthread-core-ha-config-posix.h
+++ b/openthread_border_router/openthread-core-ha-config-posix.h
@@ -83,4 +83,18 @@
  */
 #define OPENTHREAD_CONFIG_MULTICAST_DNS_AUTO_ENABLE_ON_INFRA_IF 0
 
+/**
+ * @def OPENTHREAD_POSIX_CONFIG_UPSTREAM_DNS_BIND_TO_INFRA_NETIF
+ *
+ * The app runs with host networking; the upstream DNS server from
+ * /etc/resolv.conf (Supervisor CoreDNS, 172.30.32.3) is only reachable
+ * through the hassio bridge, not through the infra interface. Binding the
+ * upstream DNS resolver socket to the infra interface (OpenThread default
+ * since commit d88b63d19, first shipped in app 2.12.0) misroutes those
+ * queries out the physical interface, breaking upstream DNS/DNS64 for
+ * Thread devices. Disable the bind so queries follow the host routing
+ * table (see home-assistant/addons#3947).
+ */
+#define OPENTHREAD_POSIX_CONFIG_UPSTREAM_DNS_BIND_TO_INFRA_NETIF 0
+
 #endif /* OPENTHREAD_CORE_HA_CONFIG_POSIX_H_ */