GCVE-110-VULN-PYPI-2026-000589

aimarket-emporion's page capture capability (emporion.web.capture@v1, capture.capture) fetches a URL the caller chooses and refuses the host unless every address it resolves to is public (capture.pin_address, capture._public). In 0.4.0 and 0.4.1 _public unwraps only IPv4-mapped IPv6 addresses. Python's ipaddress module counts the NAT64 prefix 64:ff9b::/96 as global, so a name that resolves to 64:ff9b::a00:5, the NAT64 form of 10.0.0.5, passes the check. On a host whose network routes 64:ff9b::/96 through a NAT64 gateway, the capture then connects to that private IPv4 address and returns what it answered to the caller, with the body when it is small. On Python releases whose ipaddress module does not list 2002::/16 as private, a 6to4 form passes the same way. The same weakness in aimarket-signal-hunt is GCVE-110-PYPI-2026-021946. Affects 0.4.0 and 0.4.1. Version 0.4.2 judges IPv4-mapped, 6to4 and NAT64 addresses by the IPv4 address they carry.