CVE-2018-17877: GREEDY599 Greedy 599

High severity, CVSS 7.5. EPSS: 1.6% chance of exploitation in the next 30 days.

A lottery smart contract implementation for Greedy 599, an Ethereum gambling game, generates a random value that is predictable via an external contract call. The developer used the extcodesize() function to prevent a malicious contract from being called, but the attacker can bypass it by writing the core code in the constructor of their exploit code. Therefore, it allows attackers to always win and get rewards.

Affected products

• GREEDY599 Greedy 599: affected versions not specified

Published 2018-10-23. Last modified 2026-06-17.