CVE-2022-24787: Incorrect Comparison in Vyper

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-04-04 · updated 2026-06-17
Weakness: CWE-697

Description

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine. In version 0.3.1 and prior, bytestrings can have dirty bytes in them, resulting in the word-for-word comparisons giving incorrect results. Even without dirty nonzero bytes, two bytestrings can compare to equal if one ends with `"\x00"` because there is no comparison of the length. A patch is available and expected to be part of the 0.3.2 release. There are currently no known workarounds.

Affected products

vyperlang vyper: through 0.3.1

References

https://github.com/vyperlang/vyper/commit/2c73f8352635c0a433423a5b94740de1a118e508
https://github.com/vyperlang/vyper/security/advisories/GHSA-7vrm-3jc8-5wwm
https://github.com/vyperlang/vyper/commit/2c73f8352635c0a433423a5b94740de1a118e508
https://github.com/vyperlang/vyper/security/advisories/GHSA-7vrm-3jc8-5wwm

Get alerted when CVE-2022-24787 or the next vulnerability affects your stack