CVE-2021-48019 (GCVE-0-2021-48019)

Vulnerability from cvelistv5 – Published: 2026-10-21 00:36 – Updated: 2026-10-21 00:36
VLAI
Title
Vyper before 0.2.9 Incorrect RETURNDATASIZE in create_forwarder_to Proxies
Summary
Vyper before 0.2.9 deploys forwarder proxies through the built-in create_forwarder_to function that report a fixed 4096-byte RETURNDATASIZE rather than the actual return data size. Calls through these proxies can yield corrupted data when a function returns more than 4096 bytes without return data sanitation, and fail strict return-size checks such as SafeERC20.safeTransfer.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L
CWE
  • CWE-805 - Buffer Access with Incorrect Length Value
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6762 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
vyperlang vyper Affected: 0 , < 0.2.9 (python)
Unaffected: 0.2.9 (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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