GHSA-g2xh-c426-v8mf

Опубликовано: 04 сент. 2023

Источник: github

Github: Прошло ревью

CVSS4: 6.9

CVSS3: 5.3

Описание

Vyper: reversed order of side effects for some operations

Impact

For the following (probably non-exhaustive) list of expressions, the compiler evaluates the arguments from right to left instead of left to right.

- unsafe_add - unsafe_sub - unsafe_mul - unsafe_div - pow_mod256 - |, &, ^ (bitwise operators) - bitwise_or (deprecated) - bitwise_and (deprecated) - bitwise_xor (deprecated) - raw_call - <, >, <=, >=, ==, != - in, not in (when lhs and rhs are enums)

This behaviour becomes a problem when the evaluation of one of the arguments produces side effects that other arguments depend on. The following expressions can produce side-effect:

state modifying external call
state modifying internal call
raw_call
pop() when used on a Dynamic Array stored in the storage
create_minimal_proxy_to
create_copy_of
create_from_blueprint

For example:

f:uint256 @internal def side_effect() -> uint256: self.f = 12 return 1 @external def foo() -> uint256: return unsafe_add(self.f,self.side_effect()) # returns 13 instead of 1

a:DynArray[uint256, 12] @external def bar() -> bool: self.a = [1,2,3] return len(self.a) == self.a.pop() # return false instead of true

Patches

not yet patched, will address in a future release. tracking in https://github.com/vyperlang/vyper/issues/3604.

Workarounds

When using expressions from the list above, make sure that the arguments of the expression do not produce side effects or, if one does, that no other argument is dependent on those side effects.

References

Are there any links users can visit to find out more?

Ссылки

Пакеты

Наименование

vyper

pip

Затронутые версииВерсия исправления

<= 0.4.2

Отсутствует

EPSS

Процентиль: 22%

0.00072

Низкий

6.9 Medium

CVSS4

5.3 Medium

CVSS3

CVE ID

CVE-2023-40015

Дефекты

CWE-670

Связанные уязвимости

CVE-2023-40015

CVSS3: 3.7

nvd

больше 2 лет назад

Vyper is a Pythonic Smart Contract Language. For the following (probably non-exhaustive) list of expressions, the compiler evaluates the arguments from right to left instead of left to right. `unsafe_add, unsafe_sub, unsafe_mul, unsafe_div, pow_mod256, |, &, ^ (bitwise operators), bitwise_or (deprecated), bitwise_and (deprecated), bitwise_xor (deprecated), raw_call, <, >, <=, >=, ==, !=, in, not in (when lhs and rhs are enums)`. This behaviour becomes a problem when the evaluation of one of the arguments produces side effects that other arguments depend on. The following expressions can produce side-effect: state modifying external call , state modifying internal call, `raw_call`, `pop()` when used on a Dynamic Array stored in the storage, `create_minimal_proxy_to`, `create_copy_of`, `create_from_blueprint`. This issue has not yet been patched. Users are advised to make sure that the arguments of the expression do not produce side effects or, if one does, that no other argument is depe

EPSS

Процентиль: 22%

0.00072

Низкий

6.9 Medium

CVSS4

5.3 Medium

CVSS3

CVE ID

CVE-2023-40015

Дефекты

CWE-670