CVE-2026-111171

CVSS 6.3 (medium) · published 2026-10-15

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.

Weakness: CWE-918

Source: NVD CVE-2026-111171

References

• https://github.com/ethereum/web3.py
• https://github.com/ethereum/web3.py/blob/c8c1ed0c9e77e1a8b74902e6a6825e0b00534b10/web3/utils/ccip_url_validation.py#L16-L57
• https://github.com/ethereum/web3.py/pull/3875
• https://github.com/ethereum/web3.py/security/advisories/GHSA-5hr4-253g-cpx2
• https://www.vulncheck.com/advisories/web3-py-7.15.0-through-7.16.0-and-8.0-0b2-through-8.0.0-ccip-read-ssrf-bypass
• https://github.com/ApeWorX/web3.py/security/advisories/GHSA-5hr4-253g-cpx2

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