diff --git a/advanced_expert/vulnerabilities/replay_attacks/README.md b/advanced_expert/vulnerabilities/replay_attacks/README.md
new file mode 100644
index 0000000..a75369c
--- /dev/null
+++ b/advanced_expert/vulnerabilities/replay_attacks/README.md
@@ -0,0 +1,5 @@
+## replay attacks
+
+<br>
+
+* **[the chainID of ETHW is one of the primary causes behind its nosedive, by harbor](https://medium.com/coinmonks/one-of-the-main-reasons-for-the-ethw-nosedive-is-its-chain-id-9519623b5dc)**