Recently, a security firm discovered a stack overflow vulnerability in the Move VM that does not limit the depth of recursive calls, which can cause a total network shutdown, prevent new validator nodes from joining the network, and potentially even cause a hard fork. mainnet_v1.2.1, Aptos mainnet_v1.4.3 and earlier are all affected by this vulnerability. Suimainnet_v1.2.1, Aptosmainnet_v1.4.3, and Move-language versions after June 10, 2023 fix this vulnerability.