diff --git a/client/file_sync_client.cpp b/client/file_sync_client.cpp
index 2e8b975..8f8601b 100644
--- a/client/file_sync_client.cpp
+++ b/client/file_sync_client.cpp
@@ -544,7 +544,17 @@
 
             if (!ReadFdExactly(fd, buf, len)) return false;
             buf[len] = 0;
-
+            // Address the unlikely scenario wherein a
+            // compromised device/service might be able to
+            // traverse across directories on the host. Let's
+            // shut that door!
+            if (strchr(buf, '/')
+#if defined(_WIN32)
+                || strchr(buf, '\\')
+#endif
+            ) {
+                return false;
+            }
             callback(dent.mode, dent.size, dent.mtime, buf);
         }
     }