{"id":"CVE-2021-48019","details":"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.","aliases":["GHSA-375m-5fvv-xq23"],"modified":"2026-10-29T02:46:41.610542701Z","published":"2026-10-21T01:17:19.130Z","database_specific":{},"references":[{"type":"ADVISORY","url":"https://github.com/vyperlang/vyper/security/advisories/GHSA-375m-5fvv-xq23"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/vyper-before-0.2.9-incorrect-returndatasize-in-create-forwarder-to-proxies"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/vyperlang/vyper","events":[{"introduced":"0"},{"fixed":"2647ea9033f47011ab0904ac0b3b6c51ca2f76eb"}],"database_specific":{"extracted_events":[{"source":"DESCRIPTION","range":[{"introduced":"0"},{"fixed":"0.2.9"}]}]}}],"versions":["v0.2.8","v0.2.7","v0.2.6","v0.2.5","v0.2.4","v0.2.3","v0.2.2","v0.2.1","0.2.1","v0.2.0","v0.1.0-beta.17","v0.1.0-beta.16","v0.1.0-beta.15","v0.1.0-beta.14","v0.1.0-beta.13","v0.1.0-beta.12","v0.1.0-beta.11","v0.1.0-beta.10","v0.1.0-beta.9","v0.1.0-beta.8","v0.1.0-beta.7","v0.1.0-beta.6","v0.1.0-beta.5","v0.1.0-beta.3","v0.1.0-beta.2","v0.1.0-beta.1","v0.0.4"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-48019.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}