CVE-2023-32058
Vyper vulnerable to integer overflow in loop
Impact
### Impact Due to missing overflow check for loop variables, by assigning the iterator of a loop to a variable, it is possible to overflow the type of the latter. In the following example, calling `test` returns `354`, meaning that the variable `a` did store `354` a value out of bound for the type `uint8`. ```Vyper @external def test() -> uint16: x:uint8 = 255 a:uint8 = 0 for i in range(x, x+100): a = i return convert(a,uint16) ``` The issue seems to happen only in loops of type `for i in range(a, a + N)` as in loops of type `for i in range(start, stop)` and `for i in range(stop)`, the compiler is able to raise a `TypeMismatch` when trying to overflow the variable. thanks to @trocher for reporting ### Patches patched in 3de1415ee77a9244eb04bdb695e249d3ec9ed868 ### Workarounds
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | vyper | < 0.3.8 | 0.3.8 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Vyperlang | Vyper | before 0.3.8 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/vyperlang/vyper/commit/3de1415ee77a9244eb04bdb695e249d3ec9ed868
- https://github.com/vyperlang/vyper/security/advisories/GHSA-6r8q-pfpv-7cgj
- https://github.com/advisories/GHSA-6r8q-pfpv-7cgj
- https://nvd.nist.gov/vuln/detail/CVE-2023-32058
- https://github.com/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2023-78.yaml