Medium 6.3Published Sep 28, 2026

CVE-2026-101912ip-address: isInSubnet() and isHostInSubnet() compare addresses of different families as if they shared an address space, allowing an allowlist check to admit an address outside its range

Updated under an hour ago (2026-10-19 09:40 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for beaugunderson ip-address

Exploited in the last 30 days

ip-address is a library for parsing and manipulating IPv4 and IPv6 addresses in JavaScript. Prior to 10.7.1, the isInSubnet and isHostInSubnet methods in src/common.ts compare masked binary strings without validating that both operands use the same IP family. A cross-family containment check whose leading address bits match makes the masked strings compare equal even though IPv4 and IPv6 do not share an address space. An allowlist or denylist decision can therefore classify an address outside the intended range as contained. This issue is fixed in version 10.7.1.

CVSS: 6.3 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Weakness (CWE): CWE-697, CWE-843
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Sep 28, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

beaugunderson ip-address beaugunderson:ip_address (from the name)	before 10.7.1	CNA record

References

https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcvx-refsource-confirm
https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28x-refsource-misc
https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.