diff --git a/api/src/main/kotlin/controller/FriendController.kt b/api/src/main/kotlin/controller/FriendController.kt
index d8b9b3db..726993c9 100644
--- a/api/src/main/kotlin/controller/FriendController.kt
+++ b/api/src/main/kotlin/controller/FriendController.kt
@@ -102,5 +102,15 @@ class FriendController(
     suspend fun acceptFriendByLink(
         @CurrentUser user: User,
         @PathVariable requestToken: String,
-    ) = friendService.acceptFriendByLink(user.id!!, requestToken)
+    ) = friendService
+        .acceptFriendByLink(user.id!!, requestToken)
+        .let { (friend, partner) ->
+            FriendResponse(
+                id = friend.id!!,
+                userId = partner.id!!,
+                displayName = friend.getPartnerDisplayName(user.id!!),
+                nickname = userNicknameService.getNicknameDto(partner.nickname),
+                createdAt = friend.createdAt,
+            )
+        }
 }
diff --git a/build.gradle.kts b/build.gradle.kts
index 57b16d23..afbb791b 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -36,6 +36,15 @@ subprojects {
         imports {
             mavenBom("org.springframework.boot:spring-boot-dependencies:4.0.1")
         }
+        dependencies {
+            // Downgrade MongoDB driver to avoid ByteBuf leak (JAVA-6038)
+            dependency("org.mongodb:mongodb-driver-core:5.5.2")
+            dependency("org.mongodb:mongodb-driver-sync:5.5.2")
+            dependency("org.mongodb:mongodb-driver-reactivestreams:5.5.2")
+            dependency("org.mongodb:bson:5.5.2")
+            dependency("org.mongodb:bson-record-codec:5.5.2")
+            dependency("org.mongodb:bson-kotlin:5.5.2")
+        }
     }
 
     tasks.withType<KotlinCompile> {