Description
Web3.py 7.15.0 through 7.16.0 and 8.0.0b2 through 8.0.0 contains a server-side request forgery vulnerability because _check_ip_blocked() does not unwrap IPv4-mapped IPv6 addresses in CCIP Read URL validation. Malicious contracts can return OffchainLookup URLs with IPv4-mapped IPv6 hosts or AAAA records, making clients with CCIP Read enabled send requests to loopback, private, or link-local services.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| ethereum | web3.py | 7.15.0 – ≤ 7.16.0, 8.0.0b2 – ≤ 8.0.0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | web3 | >= 6.0.0b3, < 7.15.0 | 7.15.0 | GHSA-5hr4-253g-cpx2 |
| PyPI | web3 | >= 8.0.0b1, < 8.0.0b2 | 8.0.0b2 | GHSA-5hr4-253g-cpx2 |
| PyPI | web3 | >= 6.0.0b3, < 7.15.0 · >= 8.0.0b1, < 8.0.0b2 | 7.15.0, 8.0.0b2 | PYSEC-2026-3414 |
References
- https://github.com/ethereum/web3.py/pull/3875 issue-tracking technical-description patch
- https://github.com/ethereum/web3.py/blob/c8c1ed0c9e77e1a8b74902e6a6825e0b00534b10/web3/utils/ccip_url_validation.py#L16-L57 technical-description
- GitHub Security Advisory (GHSA-5hr4-253g-cpx2) related vendor-advisory
- https://github.com/ethereum/web3.py product
- VulnCheck Advisory: Web3.py 7.15.0 through 7.16.0 and 8.0.0b2 through 8.0.0 CCIP-Read SSRF Bypass third-party-advisory