CVE 1.7 LOW

web3.py affected by SSRF via CCIP Read (EIP-3668) OffchainLookup URL handling_CVE-2026-40072

1.7 / 10
LOW
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U

Description

web3.py allows you to interact with the Ethereum blockchain using Python. From 6.0.0b3 to before 7.15.0 and 8.0.0b2, web3.py implements CCIP Read / OffchainLookup (EIP-3668) by performing HTTP requests to URLs supplied by smart contracts in offchain_lookup_payload["urls"]. The implementation uses these contract-supplied URLs directly (after {sender} / {data} template substitution) without any destination validation. CCIP Read is enabled by default (global_ccip_read_enabled = True on all providers), meaning any application using web3.py's .call() method is exposed without explicit opt-in. This results in Server-Side Request Forgery (SSRF) when web3.py is used in backend services, indexers, APIs, or any environment that performs eth_call / .call() against untrusted or user-supplied contract addresses. A malicious contract can force the web3.py process to issue HTTP requests to arbitrary destinations, including internal network services and cloud metadata endpoints. This vulnerability is fixed in 7.15.0 and 8.0.0b2.

Basic Information

ID CVE-2026-40072
Source GitHub_M
Published Apr 9, 2026 at 17:41
Modified Apr 9, 2026 at 19:37

Affected Product

Vendor ethereum
Product web3.py
Version >= 6.0.0b3, < 7.15.0
Affected Versions ethereum web3.py >= 6.0.0b3, < 7.15.0
ethereum web3.py >= 8.0.0b1, < 8.0.0b2

CWE Classification

References

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