CVE-2023-30629 – Vyper's raw_call with outsize=0 and revert_on_failure=False returns incorrect success value

https://notcve.org/view.php?id=CVE-2023-30629

Vyper is a Pythonic Smart Contract Language for the ethereum virtual machine. In versions 0.3.1 through 0.3.7, the Vyper compiler generates the wrong bytecode. Any contract that uses the `raw_call` with `revert_on_failure=False` and `max_outsize=0` receives the wrong response from `raw_call`. Depending on the memory garbage, the result can be either `True` or `False`. A patch is available and, as of time of publication, anticipated to be part of Vyper 0.3.8. • https://docs.vyperlang.org/en/v0.3.7/built-in-functions.html#raw_call https://github.com/lidofinance/gate-seals/blob/051593e74df01a4131c485b4fda52e691cd4b7d8/contracts/GateSeal.vy#L164 https://github.com/lidofinance/gate-seals/pull/5/files https://github.com/vyperlang/vyper/commit/851f7a1b3aa2a36fd041e3d0ed38f9355a58c8ae https://github.com/vyperlang/vyper/security/advisories/GHSA-w9g2-3w7p-72g9 • CWE-670: Always-Incorrect Control Flow Implementation •