CVE-2026-40072CWE-918

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

Low · published April 9, 2026

CVSS v4.0
1.7
EPSS
0%
Percentile
22.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
1.7 · LOW
Vector
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
EPSS
0.00311 · 22.7th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-04-09T17:41Z
EPSS history
Timeline
  • 09 APR 17:41Z
    web3.py affected by SSRF via CCIP Read (EIP-3668) OffchainLookup URL handling
    cvelistv5