# ip-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 Advisory record · `GHSA-j6r3-76f7-8jcv` - **Identifiers:** `GHSA-j6r3-76f7-8jcv` · `CVE-2026-101912` - **State:** Confirmed - **Severity:** CVSS 6.3 Medium - **Critical:** No - **Weakness (CWE):** [CWE-697](https://cwe.mitre.org/data/definitions/697.html) · [CWE-843](https://cwe.mitre.org/data/definitions/843.html) - **Tags:** [Memory corruption](https://agentprime.io/advisories/tag/memory-corruption.md) · [CWE-697](https://agentprime.io/advisories/tag/cwe-697.md) - **Published:** 29 Sept 2026 - **Updated:** 30 Sept 2026 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 29 Sept 2026, 23:46 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Affected packages - `ip-address` (npm): affected `<10.7.1`; fixed in `10.7.1` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > Versions of the npm package ip-address up to and including 10.7.0 are affected. The isInSubnet() and isHostInSubnet() methods compare masked address bit strings without checking that both addresses belong to the same family, so an IPv4 address can match an IPv6 network or the reverse. An application that parses untrusted input and checks it against a fixed-family allowlist can therefore admit an address outside that list. Upgrade to version 10.7.1, which makes cross-family comparisons return false; callers that need cross-family comparison should convert addresses first. Written 31 Oct 2026. ## Not analysed yet We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check. ## Severity and exploitation - 6.3 Medium, CVSS 4.0: `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`, from CNA (GitHub_M) - **CISA KEV:** Not listed. - **EPSS:** 0.0037, the 31st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 31 Oct 2026, 13:34 UTC: First seen by agentprime - 31 Oct 2026, 13:34 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-j6r3-76f7-8jcv) ## Sources - [GitHub Advisory Database: GHSA-j6r3-76f7-8jcv](https://github.com/advisories/GHSA-j6r3-76f7-8jcv) - [OSV: GHSA-j6r3-76f7-8jcv](https://osv.dev/vulnerability/GHSA-j6r3-76f7-8jcv) - - - - - Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code. ## Check whether this affects you A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet. - With the agentprime MCP server (), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .