CVE-2021-48019
Published:October 21, 2026
Updated:October 21, 2026
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.
Affected Packages
https://github.com/vyperlang/vyper.git (GITHUB):
Affected version(s) >=v0.1.0-beta.1 <v0.2.9Fix Suggestion:
Update to version v0.2.9vyper (PYTHON):
Affected version(s) >=0.1.0b1 <0.2.9Fix Suggestion:
Update to version 0.2.9Related Resources (2)
Do you need more information?
Contact UsCVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
Buffer Access with Incorrect Length Value