{"id":"EUVD-2026-88396","revision":null,"records":[{"revision":"d2b38a584ae742b3bce3d883ed98934f","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-101912","aliases":[],"title":"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","description":"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.","state":0,"publishedAt":"2026-09-28T17:48:06.99+00:00","modifiedAt":"2026-09-28T19:13:25.495+00:00","affected":[{"ecosystem":"Vendor product","name":"ip-address","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"beaugunderson\",\n                    \"product\": \"ip-address\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 10.7.1\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"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","score":6.3,"severity":"MEDIUM"}],"references":["https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcv","https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28","https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-101912","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-101912","identifiers":["CVE-2026-101912"]},"retained":false,"historicalAffected":[]},{"revision":"98165b478da84bbe8be226497c168cfd","observedAt":"2026-11-11T05:28:24.089+00:00","statement":{"source":"euvd","id":"EUVD-2026-88396","aliases":["CVE-2026-101912","GHSA-j6r3-76f7-8jcv"],"title":"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 …","description":"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.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 4.0","vector":"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","score":6.3,"severity":null}],"references":["https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcv","https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28","https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-88396","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Sep 28, 2026, 5:48:06 PM","dateUpdated":"Sep 28, 2026, 7:13:25 PM"},"relatedAdvisories":[],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-88396","identifiers":["EUVD-2026-88396","CVE-2026-101912","GHSA-j6r3-76f7-8jcv"]},"retained":false,"historicalAffected":[]},{"revision":"e99f04353d0441129174bb0106acda6a","observedAt":"2026-10-25T04:17:26.915+00:00","statement":{"source":"nvd","id":"CVE-2026-101912","aliases":[],"title":"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 …","description":"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.","state":0,"publishedAt":"2026-09-28T18:17:21.073+00:00","modifiedAt":"2026-09-30T19:57:08.043+00:00","affected":[],"metrics":[{"system":"CVSS 4.0 · security-advisories@github.com · Secondary","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","score":6.3,"severity":"MEDIUM"}],"references":["https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28","https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1","https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcv"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-101912","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-697","CWE-843"],"productCriteria":[],"sourceDates":{"published":"2026-09-28T18:17:21.073","lastModified":"2026-09-30T19:57:08.043"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-101912","identifiers":["CVE-2026-101912"]},"retained":false,"historicalAffected":[]},{"revision":"80f23b9e4b484415acb97afb0c898e17","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-j6r3-76f7-8jcv","aliases":["CVE-2026-101912"],"title":"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","description":"### Summary\n\n`isInSubnet()` and `isHostInSubnet()` accept an address of either family and compare masked binary strings without checking that both operands are the same family. `Address4` pads to 32 bits and `Address6` to 128, so whenever the leading bits agree the strings are equal: `new Address6('a00::1').isInSubnet(new Address4('10.0.0.0/8'))` is `true`, and `new Address4('32.0.0.1').isInSubnet(new Address6('2000::/3'))` is `true`. No IPv4 address is inside an IPv6 network, so both answers are untrue.\n\nAn application that parses untrusted input as whichever family accepts it and then tests the result against a fixed-family allowlist can admit an address outside the list.\n\n### Details\n\nBoth methods are in `src/common.ts`:\n\n```ts\nexport function isInSubnet(this: Address4 | Address6, address: Address4 | Address6) {\n  if (this.subnetMask < address.subnetMask) {\n    return false;\n  }\n\n  return isHostInSubnet.call(this, address);\n}\n\nexport function isHostInSubnet(this: Address4 | Address6, address: Address4 | Address6) {\n  return this.mask(address.subnetMask) === address.mask();\n}\n```\n\n`mask(n)` returns the first `n` bits of the address as a string of `0` and `1`, taken from a representation padded to the family's width. `new Address6('a00::1').mask(8)` is `'00001010'`, and so is `new Address4('10.0.0.0/8').mask()`, so string equality reports containment. The signature admits either family on either side, so TypeScript raises nothing, and the `v4` property on `Address6` marks IPv4 notation (`::ffff:10.0.0.1`) rather than family, so it does not discriminate either.\n\nWhich cross-family pairs coincide depends on the network's prefix length. `mask(n)` on an `Address4` returns at most 32 bits, so an IPv6 network longer than `/32` never matches an IPv4 address, and an IPv6 network of `/32` or shorter matches exactly the IPv4 addresses whose leading bits equal its prefix. An IPv4 network is at most 32 bits and matches every IPv6 address whose leading bits equal its prefix.\n\n### Affected versions\n\n`<= 10.7.0`. The comparison has had this shape since the methods were written, so every release is affected.\n\n### Impact\n\n| Expression | Result | Reason |\n|---|---|---|\n| `new Address6('a00::1').isInSubnet(new Address4('10.0.0.0/8'))` | `true` | both mask to `00001010` |\n| `new Address4('10.0.0.1').isInSubnet(new Address6('a00::/8'))` | `true` | the same bits, reversed |\n| `new Address4('32.0.0.1').isInSubnet(new Address6('2000::/3'))` | `true` | both begin `001` |\n| `new Address4('32.1.13.184').isInSubnet(new Address6('2001:db8::/32'))` | `true` | the `/32` spells an IPv4 address |\n| `new Address6('cb00:7100::1').isInSubnet(new Address4('203.0.113.0/24'))` | `true` | the `/24` spells an IPv6 prefix |\n| `new Address4('10.0.0.1').isInSubnet(new Address6('::ffff:10.0.0.0/104'))` | `false` | `/104` is longer than 32 bits |\n| `new Address4('8.8.8.8').isInSubnet(new Address4('10.0.0.0/8'))` | `false` | same-family control |\n\nIn the allowlist direction the check admits an address outside the list; in the denylist direction it blocks an address outside the list. What the coincidence can admit is narrow. An IPv6 allowlist of `/32` or shorter admits the IPv4 addresses its prefix spells: `2001:db8::/32` admits exactly `32.1.13.184`, and `2000::/3` admits `32.0.0.0/3`. Those are public IPv4 addresses; the private, loopback, and link-local ranges begin with bit patterns no allocated IPv6 prefix shares. An IPv4 allowlist admits the IPv6 addresses its prefix spells, and those all sit in blocks IANA has not allocated. So a request admitted through this defect reaches an address outside the intended list, not an internal host, and the severity reflects that.\n\n### Proof of concept\n\n`npm i ip-address@10.7.0`, then:\n\n```js\nconst { Address4, Address6 } = require('ip-address');\n\n// An allowlist of the application's own IPv6 range, tested against whichever\n// family the input parses as.\nconst allowed = new Address6('2001:db8::/32');\n\nfunction parse(host) {\n  return Address4.isValid(host) ? new Address4(host) : new Address6(host);\n}\n\nfor (const h of ['2001:db8::1', '2001:db9::1', '32.1.13.184', '32.1.13.185']) {\n  console.log(parse(h).isInSubnet(allowed) ? 'ALLOW' : 'BLOCK', h);\n}\n```\n\nOn affected versions:\n\n```\nALLOW 2001:db8::1\nBLOCK 2001:db9::1\nALLOW 32.1.13.184\nBLOCK 32.1.13.185\n```\n\nThe IPv6 rows are right. The IPv4 address whose 32 bits equal the allowlist's prefix is admitted; the one next to it is not.\n\n### Remediation\n\nUpgrade to the patched release. In the fix, `isHostInSubnet()` returns `false` when the two addresses are of different families, and `isInSubnet()` inherits the answer. The methods keep accepting either family so existing call sites compile. A caller that means to compare across families converts first, with `Address6.fromAddress4()`, `to4()`, or `toAddress4Nat64()`: `new Address6('::ffff:10.0.0.1').to4().isInSubnet(new Address4('10.0.0.0/8'))` is `true`, as before.\n\nIf you cannot upgrade immediately, compare the classes before you compare the addresses:\n\n```js\nconst contained = host.constructor === network.constructor && host.isInSubnet(network);\n```\n\n### A note on SSRF defense\n\nThese methods are address classifiers, not a complete SSRF defense. Regardless of this fix, a robust SSRF guard must resolve the hostname and validate the *resolved* IP against the socket it connects to, and account for DNS rebinding and redirects. Treat these checks as one layer, not the only one.","state":0,"publishedAt":"2026-09-29T23:46:52+00:00","modifiedAt":"2026-09-30T00:00:03.8434484+00:00","affected":[{"ecosystem":"npm","name":"ip-address","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"10.7.1"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","vector":"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","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcv","https://nvd.nist.gov/vuln/detail/CVE-2026-101912","https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28","https://github.com/beaugunderson/ip-address","https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1"],"sourceUrl":"https://github.com/advisories/GHSA-j6r3-76f7-8jcv","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-j6r3-76f7-8jcv","identifiers":["GHSA-j6r3-76f7-8jcv","CVE-2026-101912"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-12T02:56:45.8822264+00:00","complete":true,"records":1779,"lastAttemptAt":"2026-11-12T02:56:45.8822264+00:00","lastSuccessAt":"2026-11-12T02:56:46.0427292+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:46.0427301+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-64752486c567b55b31fb0d7225f5222bcd0019564ac0ac5f0649e242c7b19299-c8f0a5eb97b437649f83f6fe632ec849fcb249052407d33e475e82c88b318dfb","complete":true,"records":424535,"lastAttemptAt":"2026-11-12T02:56:45.3610802+00:00","lastSuccessAt":"2026-11-12T02:56:45.341976+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.3610802+00:00","snapshotPublishedAt":"2026-11-12T02:25:26+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-3bce114846604d92838a2dc302341627","complete":false,"records":13760,"lastAttemptAt":"2026-11-12T03:06:53.8778262+00:00","lastSuccessAt":"2026-11-12T03:06:52.8+00:00","error":"754 identifier lookups failed; latest failures include AccessDenied (HTTP 403). Other identifiers were checked independently.","lastVerifiedAt":"2026-11-12T03:06:52.8+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13040,"expectedIdentifiers":13813,"failedIdentifiers":754},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-12T02:56:45.8822264+00:00","complete":true,"records":1097,"lastAttemptAt":"2026-11-12T02:56:45.8822264+00:00","lastSuccessAt":"2026-11-12T02:56:46.0434469+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:46.0434471+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-729a419ccc5f41d8a3330c7c6e8b6a5e","complete":true,"records":13760,"lastAttemptAt":"2026-11-12T02:57:11.7691852+00:00","lastSuccessAt":"2026-11-12T02:57:11.766+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:57:11.766+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13813,"expectedIdentifiers":13813,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-3562b6c78fd1bd0f0b55daf66a0926ae24f65e462df7f6d928caad458fc696bf","complete":true,"records":9947,"lastAttemptAt":"2026-11-12T02:56:45.7363501+00:00","lastSuccessAt":"2026-11-11T04:27:43.6877707+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.7363501+00:00","snapshotPublishedAt":"2026-11-11T03:32:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-456002455e0ab94bb92c95476d4e6d175c104cd594749982afd96c893728ecbc","complete":true,"records":2010,"lastAttemptAt":"2026-11-12T02:56:45.5271491+00:00","lastSuccessAt":"2026-11-11T02:36:58.1276999+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.5271491+00:00","snapshotPublishedAt":"2026-11-11T01:17:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-baa8362b4daf9e5f39d5563775a55935e7b442c0735d33274a921579ce4a0d66","complete":true,"records":3093,"lastAttemptAt":"2026-11-12T02:56:45.8443473+00:00","lastSuccessAt":"2026-11-11T13:00:02.5446881+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.8443473+00:00","snapshotPublishedAt":"2026-11-11T12:47:47+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-685fe7fb2b690656c910a1ea42a9d294e8353311ac8ecfa691a9b0ff1b328804","complete":true,"records":231695,"lastAttemptAt":"2026-11-12T02:56:45.6384803+00:00","lastSuccessAt":"2026-11-11T21:58:47.7265713+00:00","error":null,"lastVerifiedAt":"2026-11-12T02:56:45.6384803+00:00","snapshotPublishedAt":"2026-11-11T21:48:35+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}