ip-address is a library for parsing and manipulating IPv4 and IPv6 addresses in JavaScript. From 10.2.0 until 10.5.1, the Address6 isPrivate classifier in src/ipv6.ts does not recognize the NAT64 local-use range 64:ff9b:1::/48. Applications that combine isPrivate, isLoopback, and isLinkLocal for a trust-boundary decision can treat an internal IPv4 destination encoded through that range as external. Exploitation depends on a server network using an operator-selected NAT64 prefix within the local-use range. A successful bypass can cross the intended network trust boundary. This issue is fixed in version 10.5.1.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-918"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/101xxx/CVE-2026-101910.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "10.2.0"
},
{
"fixed": "10.5.1"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "ab3dc88bcf5374344168a2ba075ca7ac4ff257f8"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v10.5.1",
"range": [
{
"fixed": "38b02d73cfc0724f9ad61c65b6328e116eac03ec"
}
],
"source": "REFERENCES_TAG"
}
]
}