GitHub Advisoryadvisory · PyPI
GHSA-7vrm-3jc8-5wwm Incorrect Comparison in Vyper
HIGH
Official page ↗
- Ecosystem
- PyPI
- Packages
- vyper
- Severity
- High
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Weaknesses
- CWE-697
- Reviewed
- 2022-04-04
Affected packages
• PyPI vyper: < 0.3.2 → fixed in 0.3.2
Description
Impact
bytestrings can have dirty bytes in them, resulting in the word-for-word comparison to give incorrect results, e.g.
```vyper
b1: Bytes[32] = b"abcdef"
b1 = slice(b1, 0, 1)
b2: Bytes[32] = b"abcdef"
t: bool = b1 == b2 # incorrectly evaluates to True
```
even without dirty nonzero bytes, because there is no comparison of the length, two bytestrings can compare to equal if one ends with `"\x00"`.
```vyper
b1: Bytes[32] = b"abc\0"
b2: Bytes[32] = b"abc"
t: bool = b1 == b2 # incorrectly evaluates to True
```
Patches
fixed in https://github.com/vyperlang/vyper/commit/2c73f8352635c0a433423a5b94740de1a118e508
Related
Weakness · CWE (1)
- CWE-697 Incorrect Comparison weakness