diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index cb2c06d1a9..61976cf2f3 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -38,6 +38,26 @@ updates:
     labels:
       - dependencies
 
+    - package-ecosystem: gomod
+    directory: "/"
+    schedule:
+      interval: daily
+    target-branch: "release/v4.3.x"
+    # Only allow automated security-related dependency updates on release branches.
+    open-pull-requests-limit: 0
+    labels:
+      - dependencies
+
+  - package-ecosystem: gomod
+    directory: "/"
+    schedule:
+      interval: daily
+    target-branch: "release/v4.3.x-lsm"
+    # Only allow automated security-related dependency updates on release branches.
+    open-pull-requests-limit: 0
+    labels:
+      - dependencies
+
   - package-ecosystem: gomod
     directory: "/"
     schedule:
diff --git a/.mergify.yml b/.mergify.yml
index 6344fe199a..c5825b5bf8 100644
--- a/.mergify.yml
+++ b/.mergify.yml
@@ -26,6 +26,23 @@ pull_request_rules:
       backport:
         branches:
           - release/v4.2.x-lsm
+pull_request_rules:
+  - name: Backport patches to the release/v4.3.x branch
+    conditions:
+      - base=main
+      - label=A:backport/v4.3.x
+    actions:
+      backport:
+        branches:
+          - release/v4.3.x
+  - name: Backport patches to the release/v4.3.x-lsm branch
+    conditions:
+      - base=main
+      - label=A:backport/v4.3.x-lsm
+    actions:
+      backport:
+        branches:
+          - release/v4.3.x-lsm
   - name: Backport patches to the release/v5.x branch
     conditions:
       - base=main