TON

A Denial of Service (DoS) vulnerability was discovered in the TON Lite Server before v2024.09. The vulnerability arises from the handling of external arguments passed to locally executed "get methods." An attacker can inject a constructed Continuation object (an internal TVM type) that is normally restricted within the VM. When the TVM executes this malicious continuation, it consumes excessive CPU resources while accruing disproportionately low virtual gas costs. This "free" computation allows an attacker to monopolize the Lite Server's processing power, significantly reducing its throughput and causing a denial of service for legitimate users acting through the gateway.

A State Pollution vulnerability was discovered in the TON Virtual Machine (TVM) before v2025.04. The issue exists in the RUNVM instruction logic (VmState::run_child_vm), which is responsible for initializing child virtual machines. The operation moves critical resources (specifically libraries and log) from the parent state to a new child state in a non-atomic manner. If an Out-of-Gas (OOG) exception occurs after resources are moved but before the state transition is finalized, the parent VM retains a corrupted state where these resources are emptied/invalid. Because RUNVM supports gas isolation, the parent VM continues execution with this corrupted state, leading to unexpected behavior or denial of service within the contract's context.

A Stack Overflow vulnerability was discovered in the TON Virtual Machine (TVM) before v2024.10. The vulnerability stems from the improper handling of vmstate and continuation jump instructions, which allow for continuous dynamic tail calls. An attacker can exploit this by crafting a smart contract with deeply nested jump logic. Even within permissible gas limits, this nested execution exhausts the host process's stack space, causing the validator node to crash. This results in a Denial of Service (DoS) for the TON blockchain network.