CVE-2021-48020

high

Description

Vyper from 0.1.0b4 before 0.3.0 contains a memory corruption vulnerability caused by an incorrect stack tip pointer when internal function calls are performed inside arrays. Contracts placing internal calls in nested array elements, external call arguments, struct literals, or raw_log topics can have memory corrupted, producing incorrect contract behavior.

References

https://www.vulncheck.com/advisories/vyper-before-0.3.0-memory-corruption-via-internal-function-calls-in-arrays

https://github.com/vyperlang/vyper/security/advisories/GHSA-22wc-c9wj-6q2v

https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-34890

Details

Source: Mitre, NVD

Published: 2026-10-21

Updated: 2026-10-21

Risk Information

CVSS v2

Base Score: 6.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:C/A:P

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L

Severity: Medium

CVSS v4

Base Score: 8.3

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00284