CVE-2026-111171
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.
Does this matter?
Lower severity and a low EPSS score (0.34%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 4.0
- 6.3 MEDIUMCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.34% probability · 27th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-918
- Source
- disclosure@vulncheck.com
EPSS moved from 0.3% on 16 October 2026 to 0.3% on 26 October 2026.
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
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.