diff --git a/README.md b/README.md
index 34efd0b..d6801d8 100755
--- a/README.md
+++ b/README.md
@@ -21,6 +21,7 @@ are available in one of the list. The list can be globally enabled or disabled i
 - [lists/microsoft-azure](lists/microsoft-azure) - known Microsoft Azure Datacenter IP Ranges
 - [lists/microsoft-office365](lists/microsoft-office365) - known Office 365 URLs and IP address ranges
 - [lists/microsoft-office365-cn](lists/microsoft-office365-cn) - known Office 365 IP address ranges in China
+- [lists/microsoft-attack-simulator](lists/microsoft-attack-simulator/) - known Office 365 hostnames and IP address used for Microsoft "Attack Simulator"
 - [lists/multicast](lists/multicast) - known IPv4 multicast CIDR blocks
 - [lists/ovh-cluster](lists/ovh-cluster) - List of known OVH Cluster IP
 - [lists/public-dns-v4](lists/public-dns-v4) - IPv4 addresses and reverse of public DNS resolver