CVE-2021-48019
Vyper before 0.2.9 Incorrect RETURNDATASIZE in create_forwarder_to Proxies
CVSS Score
4.8
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-805 |
| Vendor | vyperlang |
| Product | vyper |
| Published | Oct 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
Low
Affected Versions
vyperlang / vyper
0 < 0.2.9