CVE-2021-48020 (GCVE-0-2021-48020)

Vulnerability from cvelistv5 – Published: 2026-10-21 00:36 – Updated: 2026-10-21 00:36
VLAI
Title
Vyper before 0.3.0 Memory Corruption via Internal Function Calls in Arrays
Summary
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.
Severity
8.3 (High)
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
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L
CWE
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6701 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
vyperlang vyper Affected: 0.1.0b4 , < 0.3.0 (python)
Unaffected: 0.3.0 (python)
    cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2021-04-16 00:00
Show details on NVD website
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