CVE-2021-48020

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/vyperlang/vyper/security/advisories/GHSA-22wc-c9wj-6q2v
https://www.vulncheck.com/advisories/vyper-before-0.3.0-memory-corruption-via-internal-function-calls-in-arrays

Configurations

No configuration.

History

21 Oct 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-21 01:17

Updated : 2026-10-28 16:16

NVD link : CVE-2021-48020

Mitre link : CVE-2021-48020

CVE.ORG link : CVE-2021-48020

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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