{
    "document": {
        "category": "csaf_base",
        "csaf_version": "2.0",
        "distribution": {
            "tlp": {
                "label": "WHITE"
            }
        },
        "lang": "en",
        "notes": [
            {
                "category": "legal_disclaimer",
                "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
            }
        ],
        "publisher": {
            "category": "coordinator",
            "contact_details": "cert@ncsc.nl",
            "name": "National Cyber Security Centre",
            "namespace": "https://www.ncsc.nl/"
        },
        "title": "CVE-2026-101912",
        "tracking": {
            "current_release_date": "2026-10-02T05:28:53.112182Z",
            "generator": {
                "date": "2026-02-17T15:00:00Z",
                "engine": {
                    "name": "V.E.L.M.A",
                    "version": "1.7"
                }
            },
            "id": "CVE-2026-101912",
            "initial_release_date": "2026-09-28T18:29:03.717658Z",
            "revision_history": [
                {
                    "date": "2026-09-28T18:29:03.717658Z",
                    "number": "1",
                    "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (3).| CWES updated (1)."
                },
                {
                    "date": "2026-09-28T18:29:05.114211Z",
                    "number": "2",
                    "summary": "NCSC Score created."
                },
                {
                    "date": "2026-09-28T18:38:39.047061Z",
                    "number": "3",
                    "summary": "CVSS created.| CWES created (2).| Products created (1).| References created (3).| Description created for source.| Unknown change."
                },
                {
                    "date": "2026-09-28T18:38:50.219603Z",
                    "number": "4",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-09-28T19:38:34.482837Z",
                    "number": "5",
                    "summary": "Unknown change."
                },
                {
                    "date": "2026-09-29T00:45:04.884266Z",
                    "number": "6",
                    "summary": "Source created.| CVE status created. (valid)| Products connected (1)."
                },
                {
                    "date": "2026-09-29T06:38:16.344937Z",
                    "number": "7",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (58).| References created (5).| CWES updated (1)."
                },
                {
                    "date": "2026-09-29T06:43:53.937991Z",
                    "number": "8",
                    "summary": "Description created for source."
                },
                {
                    "date": "2026-09-29T12:29:40.748706Z",
                    "number": "9",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (4).| Product Identifiers created (1).| References created (5).| CWES updated (1).| Vendor_assessment created."
                },
                {
                    "date": "2026-09-29T12:29:45.405195Z",
                    "number": "10",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-09-29T16:12:55.827401Z",
                    "number": "11",
                    "summary": "EPSS created.| Unknown change."
                },
                {
                    "date": "2026-09-29T18:31:45.833783Z",
                    "number": "12",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-09-30T00:39:58.224013Z",
                    "number": "13",
                    "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (5).| CWES updated (1)."
                },
                {
                    "date": "2026-09-30T00:40:01.916631Z",
                    "number": "14",
                    "summary": "NCSC Score updated."
                },
                {
                    "date": "2026-10-02T05:28:45.848317Z",
                    "number": "15",
                    "summary": "NCSC Score updated."
                }
            ],
            "status": "interim",
            "version": "15"
        }
    },
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                                "name": "vers:rpm/1",
                                "product": {
                                    "name": "vers:rpm/1",
                                    "product_id": "CSAFPID-6014972",
                                    "product_identification_helper": {
                                        "cpe": "cpe:/a:redhat:hummingbird:1"
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                                "category": "product_name",
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                                "category": "product_name",
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                                    "name": "vers:unknown/v10.2.1",
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                            },
                            {
                                "category": "product_version_range",
                                "name": "vers:unknown/v10.2.2",
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                            },
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                                "category": "product_version_range",
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                            },
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                                "category": "product_version_range",
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                                    "name": "vers:unknown/v10.7.0",
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                                "category": "product_version_range",
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                    }
                ],
                "category": "vendor",
                "name": "debian"
            }
        ]
    },
    "vulnerabilities": [
        {
            "cve": "CVE-2026-101912",
            "cwe": {
                "id": "CWE-843",
                "name": "Access of Resource Using Incompatible Type ('Type Confusion')"
            },
            "notes": [
                {
                    "category": "description",
                    "text": "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.",
                    "title": "nvd - https://nvd.nist.gov/vuln/detail/CVE-2026-101912"
                },
                {
                    "category": "description",
                    "text": "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.",
                    "title": "cveprojectv5 - https://www.cve.org/CVERecord?id=CVE-2026-101912"
                },
                {
                    "category": "description",
                    "text": "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.",
                    "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-101912.json?alt=media"
                },
                {
                    "category": "description",
                    "text": "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.",
                    "title": "debian - https://security-tracker.debian.org/tracker/CVE-2026-101912"
                },
                {
                    "category": "description",
                    "text": "A flaw was found in the ip-address library. This vulnerability allows a remote attacker to bypass security restrictions, such as Internet Protocol (IP) allowlists or denylists. The library's subnet containment checks fail to verify whether the compared addresses belong to the same address family, comparing IPv4 and IPv6 addresses as if they shared an address space. As a result, an attacker can provide an address from a different IP family with matching leading bits, causing an unauthorized address outside the intended range to be treated as valid.",
                    "title": "redhat - https://access.redhat.com/security/cve/CVE-2026-101912"
                },
                {
                    "category": "description",
                    "text": "### 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.",
                    "title": "github - https://github.com/advisories/GHSA-j6r3-76f7-8jcv"
                },
                {
                    "category": "other",
                    "text": "0.0037",
                    "title": "EPSS"
                },
                {
                    "category": "other",
                    "text": "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",
                    "title": "CVSSV4"
                },
                {
                    "category": "other",
                    "text": "6.3",
                    "title": "CVSSV4 base score"
                },
                {
                    "category": "other",
                    "text": "4.3",
                    "title": "NCSC Score"
                },
                {
                    "category": "other",
                    "text": "There is cwe data available from source Nvd, Is related to (a version of) an uncommon product",
                    "title": "NCSC Score top decreasing factors"
                },
                {
                    "category": "details",
                    "text": "Severity: 2\n",
                    "title": "Vendor assessment"
                }
            ],
            "product_status": {
                "known_affected": [
                    "CSAFPID-9482861",
                    "CSAFPID-7088727",
                    "CSAFPID-8057696",
                    "CSAFPID-8057697",
                    "CSAFPID-8057698",
                    "CSAFPID-8603574",
                    "CSAFPID-8603575",
                    "CSAFPID-8603576",
                    "CSAFPID-8603577",
                    "CSAFPID-8603578",
                    "CSAFPID-8603579",
                    "CSAFPID-8603580",
                    "CSAFPID-8603581",
                    "CSAFPID-8603582",
                    "CSAFPID-8603583",
                    "CSAFPID-8603584",
                    "CSAFPID-8603585",
                    "CSAFPID-8603586",
                    "CSAFPID-8603587",
                    "CSAFPID-8603588",
                    "CSAFPID-8603589",
                    "CSAFPID-8603590",
                    "CSAFPID-8603591",
                    "CSAFPID-8603592",
                    "CSAFPID-8603593",
                    "CSAFPID-8603594",
                    "CSAFPID-8603595",
                    "CSAFPID-8603596",
                    "CSAFPID-8603597",
                    "CSAFPID-8603598",
                    "CSAFPID-8603599",
                    "CSAFPID-8603600",
                    "CSAFPID-8603601",
                    "CSAFPID-8603602",
                    "CSAFPID-8603603",
                    "CSAFPID-8603604",
                    "CSAFPID-8603605",
                    "CSAFPID-8603606",
                    "CSAFPID-8603607",
                    "CSAFPID-8603608",
                    "CSAFPID-8603609",
                    "CSAFPID-8603610",
                    "CSAFPID-8603611",
                    "CSAFPID-8603612",
                    "CSAFPID-8603613",
                    "CSAFPID-8603614",
                    "CSAFPID-8603615",
                    "CSAFPID-8603616",
                    "CSAFPID-8603617",
                    "CSAFPID-8901868",
                    "CSAFPID-8923137",
                    "CSAFPID-8932679",
                    "CSAFPID-8932680",
                    "CSAFPID-8932681",
                    "CSAFPID-9485007",
                    "CSAFPID-9485008",
                    "CSAFPID-9485009",
                    "CSAFPID-9485059",
                    "CSAFPID-9485060",
                    "CSAFPID-9485061",
                    "CSAFPID-6014972",
                    "CSAFPID-8902830",
                    "CSAFPID-8902831",
                    "CSAFPID-9053231"
                ]
            },
            "references": [
                {
                    "category": "external",
                    "summary": "Source - nvd",
                    "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Source - ncscclear",
                    "url": "https://vulnerabilities.ncsc.nl/manual/CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Source - cveprojectv5",
                    "url": "https://www.cve.org/CVERecord?id=CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Source - debian",
                    "url": "https://security-tracker.debian.org/tracker/CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Source - osv",
                    "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-101912.json?alt=media"
                },
                {
                    "category": "external",
                    "summary": "Source - redhat",
                    "url": "https://access.redhat.com/security/cve/CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Source - first",
                    "url": "https://api.first.org/data/v1/epss"
                },
                {
                    "category": "external",
                    "summary": "Source - github",
                    "url": "https://github.com/advisories/GHSA-j6r3-76f7-8jcv"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd; osv; redhat",
                    "url": "https://github.com/beaugunderson/ip-address/commit/1343629d57fea413644a5c9d41ff1e59619f3f28"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd; osv; redhat",
                    "url": "https://github.com/beaugunderson/ip-address/releases/tag/v10.7.1"
                },
                {
                    "category": "external",
                    "summary": "Reference - cveprojectv5; github; nvd; osv; redhat",
                    "url": "https://github.com/beaugunderson/ip-address/security/advisories/GHSA-j6r3-76f7-8jcv"
                },
                {
                    "category": "external",
                    "summary": "Reference - osv",
                    "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/101xxx/CVE-2026-101912.json"
                },
                {
                    "category": "external",
                    "summary": "Reference - github; osv; redhat",
                    "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Reference - redhat",
                    "url": "https://www.cve.org/CVERecord?id=CVE-2026-101912"
                },
                {
                    "category": "external",
                    "summary": "Reference - github",
                    "url": "https://github.com/advisories/GHSA-j6r3-76f7-8jcv"
                }
            ],
            "scores": [
                {
                    "cvss_v3": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                        "baseScore": 5.3,
                        "baseSeverity": "MEDIUM"
                    },
                    "products": [
                        "CSAFPID-6014972",
                        "CSAFPID-7088727",
                        "CSAFPID-8057696",
                        "CSAFPID-8057697",
                        "CSAFPID-8057698",
                        "CSAFPID-8603574",
                        "CSAFPID-8603575",
                        "CSAFPID-8603576",
                        "CSAFPID-8603577",
                        "CSAFPID-8603578",
                        "CSAFPID-8603579",
                        "CSAFPID-8603580",
                        "CSAFPID-8603581",
                        "CSAFPID-8603582",
                        "CSAFPID-8603583",
                        "CSAFPID-8603584",
                        "CSAFPID-8603585",
                        "CSAFPID-8603586",
                        "CSAFPID-8603587",
                        "CSAFPID-8603588",
                        "CSAFPID-8603589",
                        "CSAFPID-8603590",
                        "CSAFPID-8603591",
                        "CSAFPID-8603592",
                        "CSAFPID-8603593",
                        "CSAFPID-8603594",
                        "CSAFPID-8603595",
                        "CSAFPID-8603596",
                        "CSAFPID-8603597",
                        "CSAFPID-8603598",
                        "CSAFPID-8603599",
                        "CSAFPID-8603600",
                        "CSAFPID-8603601",
                        "CSAFPID-8603602",
                        "CSAFPID-8603603",
                        "CSAFPID-8603604",
                        "CSAFPID-8603605",
                        "CSAFPID-8603606",
                        "CSAFPID-8603607",
                        "CSAFPID-8603608",
                        "CSAFPID-8603609",
                        "CSAFPID-8603610",
                        "CSAFPID-8603611",
                        "CSAFPID-8603612",
                        "CSAFPID-8603613",
                        "CSAFPID-8603614",
                        "CSAFPID-8603615",
                        "CSAFPID-8603616",
                        "CSAFPID-8603617",
                        "CSAFPID-8901868",
                        "CSAFPID-8902830",
                        "CSAFPID-8902831",
                        "CSAFPID-8923137",
                        "CSAFPID-8932679",
                        "CSAFPID-8932680",
                        "CSAFPID-8932681",
                        "CSAFPID-9053231",
                        "CSAFPID-9482861",
                        "CSAFPID-9485007",
                        "CSAFPID-9485008",
                        "CSAFPID-9485009",
                        "CSAFPID-9485059",
                        "CSAFPID-9485060",
                        "CSAFPID-9485061"
                    ]
                }
            ],
            "title": "CVE-2026-101912"
        }
    ]
}