{ "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-2026-16221", "tracking": { "current_release_date": "2026-08-24T11:02:25.662298Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-16221", "initial_release_date": "2026-07-19T14:52:13.382521Z", "revision_history": [ { "date": "2026-07-19T14:52:13.382521Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (6).| References created (2).| CWES updated (1)." }, { "date": "2026-07-19T14:52:30.856241Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-07-19T15:25:19.259099Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-07-19T15:25:22.661251Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-07-19T15:36:25.842720Z", "number": "5", "summary": "NCSC Score updated." }, { "date": "2026-07-20T12:44:47.853329Z", "number": "6", "summary": "Source created.| CVE status created. (valid)| Description created for source.| Products connected (2)." }, { "date": "2026-07-20T16:15:15.617663Z", "number": "7", "summary": "Unknown change." }, { "date": "2026-07-21T05:30:21.188398Z", "number": "8", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-07-21T05:30:26.028129Z", "number": "9", "summary": "NCSC Score updated." }, { "date": "2026-07-21T22:41:23.771738Z", "number": "10", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (10).| CWES updated (1)." }, { "date": "2026-07-21T22:41:25.469339Z", "number": "11", "summary": "NCSC Score updated." }, { "date": "2026-07-22T00:23:37.582363Z", "number": "12", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (3).| References created (9).| CWES updated (1)." }, { "date": "2026-07-22T12:54:17.712408Z", "number": "13", "summary": "Products connected (2).| Products removed (2)." }, { "date": "2026-07-22T12:54:23.233731Z", "number": "14", "summary": "NCSC Score updated." }, { "date": "2026-07-22T19:01:34.348543Z", "number": "15", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-07-22T19:01:36.187758Z", "number": "16", "summary": "NCSC Score updated." }, { "date": "2026-07-25T07:00:21.373282Z", "number": "17", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (5).| Products connected (13).| References created (4).| CWES updated (1)." }, { "date": "2026-07-25T07:00:27.229611Z", "number": "18", "summary": "NCSC Score updated." }, { "date": "2026-08-05T19:33:24.460196Z", "number": "19", "summary": "Source created.| CVE status created. (valid)| Description created for source.| Products connected (14).| Product Identifiers created (9).| References created (3)." }, { "date": "2026-08-05T19:33:33.811011Z", "number": "20", "summary": "NCSC Score updated." }, { "date": "2026-08-05T20:25:20.347076Z", "number": "21", "summary": "Products created (3).| Product Identifiers created (3)." }, { "date": "2026-08-05T20:25:22.362898Z", "number": "22", "summary": "NCSC Score updated." }, { "date": "2026-08-19T12:06:12.128055Z", "number": "23", "summary": "Source connected.| CVE status created. (valid)| Products connected (11).| References created (3)." }, { "date": "2026-08-19T12:06:14.404658Z", "number": "24", "summary": "NCSC Score updated." }, { "date": "2026-08-19T16:30:43.828971Z", "number": "25", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-08-19T16:32:55.043215Z", "number": "26", "summary": "NCSC Score updated." }, { "date": "2026-08-24T09:53:09.571494Z", "number": "27", "summary": "Source connected.| CVE status created. (valid)" }, { "date": "2026-08-24T09:53:25.620000Z", "number": "28", "summary": "NCSC Score updated." } ], "status": "interim", "version": "28" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/data center lts <10.2.22", "product": { "name": "vers:unknown/data center lts <10.2.22", "product_id": "CSAFPID-9012403" } }, { "category": "product_version_range", "name": "vers:unknown/data center lts <12.1.10", "product": { "name": "vers:unknown/data center lts <12.1.10", "product_id": "CSAFPID-9012404" } } ], "category": "product_name", "name": "Bamboo" }, { "branches": [ { "category": "product_version_range", "name": "vers:unknown/data center <10.4.2", "product": { "name": "vers:unknown/data center <10.4.2", "product_id": "CSAFPID-9012406" } }, { "category": "product_version_range", "name": "vers:unknown/data center lts <10.2.6", "product": { "name": "vers:unknown/data center lts <10.2.6", "product_id": "CSAFPID-9012408" } }, { "category": "product_version_range", "name": "vers:unknown/data center lts <9.4.23", "product": { "name": "vers:unknown/data center lts <9.4.23", "product_id": "CSAFPID-9012407" } } ], "category": "product_name", "name": "Bitbucket" }, { "branches": [ { "category": "product_version_range", "name": "vers:unknown/data center lts <10.2.15", "product": { "name": "vers:unknown/data center lts <10.2.15", "product_id": "CSAFPID-9012410" } }, { "category": "product_version_range", "name": "vers:unknown/data center lts <9.2.23", "product": { "name": "vers:unknown/data center lts <9.2.23", "product_id": "CSAFPID-9012409" } } ], "category": "product_name", "name": "Confluence" }, { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<4.9.13", "product": { "name": "vers:unknown/<4.9.13", "product_id": "CSAFPID-9012413" } } ], "category": "product_name", "name": "Crucible" }, { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<4.9.13", "product": { "name": "vers:unknown/<4.9.13", "product_id": "CSAFPID-9012411" } } ], "category": "product_name", "name": "Fisheye" }, { "branches": [ { "category": "product_version_range", "name": "vers:unknown/data center lts <10.3.24", "product": { "name": "vers:unknown/data center lts <10.3.24", "product_id": "CSAFPID-9012405" } }, { "category": "product_version_range", "name": "vers:unknown/data center lts <11.3.10", "product": { "name": "vers:unknown/data center lts <11.3.10", "product_id": "CSAFPID-9012414" } } ], "category": "product_name", "name": "Jira" } ], "category": "vendor", "name": "Atlassian" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:semver/2.3.1|<2.4.3", "product": { "name": "vers:semver/2.3.1|<2.4.3", "product_id": "CSAFPID-8862648" } }, { "category": "product_version_range", "name": "vers:semver/2.4.3", "product": { "name": "vers:semver/2.4.3", "product_id": "CSAFPID-8862649" } }, { "category": "product_version_range", "name": "vers:semver/3.0.0|<3.1.4", "product": { "name": "vers:semver/3.0.0|<3.1.4", "product_id": "CSAFPID-8862650" } }, { "category": "product_version_range", "name": "vers:semver/3.1.4", "product": { "name": "vers:semver/3.1.4", "product_id": "CSAFPID-8862651" } }, { "category": "product_version_range", "name": "vers:semver/4.0.0|<4.1.1", "product": { "name": "vers:semver/4.0.0|<4.1.1", "product_id": "CSAFPID-8862652" } }, { "category": "product_version_range", "name": "vers:semver/4.1.1", "product": { "name": "vers:semver/4.1.1", "product_id": "CSAFPID-8862653" } } ], "category": "product_name", "name": "fast-uri" } ], "category": "vendor", "name": "fast-uri" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/>=2.3.1|<2.4.3", "product": { "name": "vers:unknown/>=2.3.1|<2.4.3", "product_id": "CSAFPID-8873350" } }, { "category": "product_version_range", "name": "vers:unknown/>=3.0.0|<3.1.4", "product": { "name": "vers:unknown/>=3.0.0|<3.1.4", "product_id": "CSAFPID-8873351" } }, { "category": "product_version_range", "name": "vers:unknown/>=4.0.0|<4.1.1", "product": { "name": "vers:unknown/>=4.0.0|<4.1.1", "product_id": "CSAFPID-8873352" } }, { "category": "product_version_range", "name": "vers:unknown/v2.3.1", "product": { "name": "vers:unknown/v2.3.1", "product_id": "CSAFPID-8585094" } }, { "category": "product_version_range", "name": "vers:unknown/v2.4.0", "product": { "name": "vers:unknown/v2.4.0", "product_id": "CSAFPID-8585093" } }, { "category": "product_version_range", "name": "vers:unknown/v2.4.1", "product": { "name": "vers:unknown/v2.4.1", "product_id": "CSAFPID-8895581" } }, { "category": "product_version_range", "name": "vers:unknown/v2.4.2", "product": { "name": "vers:unknown/v2.4.2", "product_id": "CSAFPID-8895579" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.0", "product": { "name": "vers:unknown/v3.0.0", "product_id": "CSAFPID-8585092" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.1", "product": { "name": "vers:unknown/v3.0.1", "product_id": "CSAFPID-8585091" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.2", "product": { "name": "vers:unknown/v3.0.2", "product_id": "CSAFPID-8585090" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.3", "product": { "name": "vers:unknown/v3.0.3", "product_id": "CSAFPID-8585089" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.4", "product": { "name": "vers:unknown/v3.0.4", "product_id": "CSAFPID-8585088" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.5", "product": { "name": "vers:unknown/v3.0.5", "product_id": "CSAFPID-8585087" } }, { "category": "product_version_range", "name": "vers:unknown/v3.0.6", "product": { "name": "vers:unknown/v3.0.6", "product_id": "CSAFPID-8585086" } }, { "category": "product_version_range", "name": "vers:unknown/v3.1.0", "product": { "name": "vers:unknown/v3.1.0", "product_id": "CSAFPID-8585085" } }, { "category": "product_version_range", "name": "vers:unknown/v3.1.1", "product": { "name": "vers:unknown/v3.1.1", "product_id": "CSAFPID-8585084" } }, { "category": "product_version_range", "name": "vers:unknown/v3.1.2", "product": { "name": "vers:unknown/v3.1.2", "product_id": "CSAFPID-8678078" } }, { "category": "product_version_range", "name": "vers:unknown/v3.1.3", "product": { "name": "vers:unknown/v3.1.3", "product_id": "CSAFPID-8895578" } }, { "category": "product_version_range", "name": "vers:unknown/v4.0.0", "product": { "name": "vers:unknown/v4.0.0", "product_id": "CSAFPID-8678079" } }, { "category": "product_version_range", "name": "vers:unknown/v4.0.1", "product": { "name": "vers:unknown/v4.0.1", "product_id": "CSAFPID-8895582" } }, { "category": "product_version_range", "name": "vers:unknown/v4.1.0", "product": { "name": "vers:unknown/v4.1.0", "product_id": "CSAFPID-8895580" } } ], "category": "product_name", "name": "fast-uri" } ], "category": "vendor", "name": "fastify" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/>=2.3.1|<2.4.3", "product": { "name": "vers:unknown/>=2.3.1|<2.4.3", "product_id": "CSAFPID-8938719", "product_identification_helper": { "cpe": "cpe:2.3:a:openjsf:fast-uri:*:*:*:*:*:node.js:*:*" } } }, { "category": "product_version_range", "name": "vers:unknown/>=3.0.0|<3.1.4", "product": { "name": "vers:unknown/>=3.0.0|<3.1.4", "product_id": "CSAFPID-8938720", "product_identification_helper": { "cpe": "cpe:2.3:a:openjsf:fast-uri:*:*:*:*:*:node.js:*:*" } } }, { "category": "product_version_range", "name": "vers:unknown/>=4.0.0|<4.1.1", "product": { "name": "vers:unknown/>=4.0.0|<4.1.1", "product_id": "CSAFPID-8938721", "product_identification_helper": { "cpe": "cpe:2.3:a:openjsf:fast-uri:*:*:*:*:*:node.js:*:*" } } } ], "category": "product_name", "name": "fast-uri" } ], "category": "vendor", "name": "openjsf" }, { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:deb/*", "product": { "name": "vers:deb/*", "product_id": "CSAFPID-8757775" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "bookworm" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:deb/*", "product": { "name": "vers:deb/*", "product_id": "CSAFPID-7469275" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "bullseye" } ], "category": "vendor", "name": "Debian" }, { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/5.0.0-1", "product": { "name": "vers:unknown/5.0.0-1", "product_id": "CSAFPID-6619736", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@5.0.0-1?arch=source&distro=bionic" } } }, { "category": "product_version_range", "name": "vers:unknown/>=0", "product": { "name": "vers:unknown/>=0", "product_id": "CSAFPID-6619737" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "Ubuntu:18.04:LTS" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/6.10.2-1", "product": { "name": "vers:unknown/6.10.2-1", "product_id": "CSAFPID-6619738", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@6.10.2-1?arch=source&distro=focal" } } }, { "category": "product_version_range", "name": "vers:unknown/>=0", "product": { "name": "vers:unknown/>=0", "product_id": "CSAFPID-6619739" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "Ubuntu:20.04:LTS" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/6.12.6-2", "product": { "name": "vers:unknown/6.12.6-2", "product_id": "CSAFPID-6619740", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@6.12.6-2?arch=source&distro=jammy" } } }, { "category": "product_version_range", "name": "vers:unknown/6.12.6-3", "product": { "name": "vers:unknown/6.12.6-3", "product_id": "CSAFPID-6619741", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@6.12.6-3?arch=source&distro=jammy" } } }, { "category": "product_version_range", "name": "vers:unknown/>=0", "product": { "name": "vers:unknown/>=0", "product_id": "CSAFPID-6619742" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "Ubuntu:22.04:LTS" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/6.12.6-3", "product": { "name": "vers:unknown/6.12.6-3", "product_id": "CSAFPID-6619743", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@6.12.6-3?arch=source&distro=noble" } } }, { "category": "product_version_range", "name": "vers:unknown/8.12.0~ds+~2.1.1-4", "product": { "name": "vers:unknown/8.12.0~ds+~2.1.1-4", "product_id": "CSAFPID-6619744", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@8.12.0~ds%2B~2.1.1-4?arch=source&distro=noble" } } }, { "category": "product_version_range", "name": "vers:unknown/>=0", "product": { "name": "vers:unknown/>=0", "product_id": "CSAFPID-6619745" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "Ubuntu:24.04:LTS" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/8.12.0~ds+~2.1.1-5", "product": { "name": "vers:unknown/8.12.0~ds+~2.1.1-5", "product_id": "CSAFPID-7765514", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@8.12.0~ds%2B~2.1.1-5?arch=source&distro=resolute" } } }, { "category": "product_version_range", "name": "vers:unknown/8.17.1~ds+~3.0.1+~3.1.0-2", "product": { "name": "vers:unknown/8.17.1~ds+~3.0.1+~3.1.0-2", "product_id": "CSAFPID-7765515", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@8.17.1~ds%2B~3.0.1%2B~3.1.0-2?arch=source&distro=resolute" } } }, { "category": "product_version_range", "name": "vers:unknown/8.17.1~ds+~3.0.1+~3.1.0-4build1", "product": { "name": "vers:unknown/8.17.1~ds+~3.0.1+~3.1.0-4build1", "product_id": "CSAFPID-7765516", "product_identification_helper": { "purl": "pkg:deb/ubuntu/node-ajv@8.17.1~ds%2B~3.0.1%2B~3.1.0-4build1?arch=source&distro=resolute" } } }, { "category": "product_version_range", "name": "vers:unknown/>=0", "product": { "name": "vers:unknown/>=0", "product_id": "CSAFPID-7765517" } } ], "category": "product_name", "name": "node-ajv" } ], "category": "product_family", "name": "Ubuntu:26.04:LTS" } ], "category": "vendor", "name": "Ubuntu" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-16221", "cwe": { "id": "CWE-436", "name": "Interpretation Conflict" }, "notes": [ { "category": "description", "text": "Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x line up to 3.1.3 and the 2.x line up to 2.4.2) do not treat a literal backslash character (U+005C) as an authority delimiter. Node's native WHATWG URL parser, used by fetch, undici, and Node's http and https clients, normalizes the backslash to a forward slash for special schemes such as http, https, ws, wss, ftp, and file. As a result, the two parsers extract different hosts from the same input string. Applications that use fast-uri to enforce host-based policy such as allowlists, denylists, loopback or SSRF filtering, redirect validation, or outbound proxy routing before passing the same URL into Node's URL or fetch consumers can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. \n\nPatches: upgrade to fast-uri 4.1.1, 3.1.4, or 2.4.3.\n\nWorkarounds: none.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-16221" }, { "category": "description", "text": "Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x line up to 3.1.3 and the 2.x line up to 2.4.2) do not treat a literal backslash character (U+005C) as an authority delimiter. Node's native WHATWG URL parser, used by fetch, undici, and Node's http and https clients, normalizes the backslash to a forward slash for special schemes such as http, https, ws, wss, ftp, and file. As a result, the two parsers extract different hosts from the same input string. Applications that use fast-uri to enforce host-based policy such as allowlists, denylists, loopback or SSRF filtering, redirect validation, or outbound proxy routing before passing the same URL into Node's URL or fetch consumers can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. \n\nPatches: upgrade to fast-uri 4.1.1, 3.1.4, or 2.4.3.\n\nWorkarounds: none.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/16xxx/CVE-2026-16221.json" }, { "category": "description", "text": "Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x line up to 3.1.3 and the 2.x line up to 2.4.2) do not treat a literal backslash character (U+005C) as an authority delimiter. Node's native WHATWG URL parser, used by fetch, undici, and Node's http and https clients, normalizes the backslash to a forward slash for special schemes such as http, https, ws, wss, ftp, and file. As a result, the two parsers extract different hosts from the same input string. Applications that use fast-uri to enforce host-based policy such as allowlists, denylists, loopback or SSRF filtering, redirect validation, or outbound proxy routing before passing the same URL into Node's URL or fetch consumers can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. Patches: upgrade to fast-uri 4.1.1, 3.1.4, or 2.4.3. Workarounds: none.", "title": "debian - https://security-tracker.debian.org/tracker/CVE-2026-16221" }, { "category": "description", "text": "### Impact\n\n`fast-uri` v4.1.0 and earlier do not treat a literal backslash (U+005C) as an authority delimiter. Node's native WHATWG `URL` (used by `fetch()`, `undici`, and Node's `http`/`https` clients) normalizes `\\` to `/` for special schemes (`http`, `https`, `ws`, `wss`, `ftp`, `file`), so the two parsers extract different hosts from the same input string.\n\nFor example, `http://evil.com\\@allowed.com` is treated by `fast-uri` as host `allowed.com` with userinfo `evil.com\\`, while Node's WHATWG URL parser and `fetch()` see host `evil.com` with path `/@allowed.com`.\n\nApplications that use `fast-uri` to enforce host-based policy (allowlists, denylists, loopback/SSRF filtering, redirect validation, outbound proxy routing) before passing the same URL into Node's URL or `fetch()` consumers see a policy/use desync and can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts.\n\n### Patches\n\nUpgrade to `fast-uri` v4.1.1, v3.1.4, or v2.4.3.\n\n### Workarounds\n\nNone. Upgrade to the patched version.", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/npm%2FGHSA-v2hh-gcrm-f6hx.json?alt=media" }, { "category": "description", "text": "### Impact\n\n`fast-uri` v4.1.0 and earlier do not treat a literal backslash (U+005C) as an authority delimiter. Node's native WHATWG `URL` (used by `fetch()`, `undici`, and Node's `http`/`https` clients) normalizes `\\` to `/` for special schemes (`http`, `https`, `ws`, `wss`, `ftp`, `file`), so the two parsers extract different hosts from the same input string.\n\nFor example, `http://evil.com\\@allowed.com` is treated by `fast-uri` as host `allowed.com` with userinfo `evil.com\\`, while Node's WHATWG URL parser and `fetch()` see host `evil.com` with path `/@allowed.com`.\n\nApplications that use `fast-uri` to enforce host-based policy (allowlists, denylists, loopback/SSRF filtering, redirect validation, outbound proxy routing) before passing the same URL into Node's URL or `fetch()` consumers see a policy/use desync and can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts.\n\n### Patches\n\nUpgrade to `fast-uri` v4.1.1, v3.1.4, or v2.4.3.\n\n### Workarounds\n\nNone. Upgrade to the patched version.", "title": "github - https://api.github.com/advisories/GHSA-v2hh-gcrm-f6hx" }, { "category": "description", "text": "Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x line up to 3.1.3 and the 2.x line up to 2.4.2) do not treat a literal backslash character (U+005C) as an authority delimiter. Node's native WHATWG URL parser, used by fetch, undici, and Node's http and https clients, normalizes the backslash to a forward slash for special schemes such as http, https, ws, wss, ftp, and file. As a result, the two parsers extract different hosts from the same input string. Applications that use fast-uri to enforce host-based policy such as allowlists, denylists, loopback or SSRF filtering, redirect validation, or outbound proxy routing before passing the same URL into Node's URL or fetch consumers can be steered to an unintended destination, including cloud metadata endpoints, loopback, or internal hosts. \n\nPatches: upgrade to fast-uri 4.1.1, 3.1.4, or 2.4.3.\n\nWorkarounds: none.", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-16221.json?alt=media" }, { "category": "description", "text": "(Impact: fast-uri versions from 2.3.1 through 4.1.0 (including the 3.x ...)", "title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Ubuntu%2FUBUNTU-CVE-2026-16221.json?alt=media" }, { "category": "other", "text": "0.00254", "title": "EPSS" }, { "category": "other", "text": "6.2", "title": "NCSC Score" }, { "category": "other", "text": "There is product data available from source Certbundde, The value of the mean historic EPSS score, There is product data available from source Nvd, Is related to (a version of) an uncommon product", "title": "NCSC Score top increasing factors" }, { "category": "other", "text": "Is related to an uncommon product vendor", "title": "NCSC Score top decreasing factors" } ], "product_status": { "known_affected": [ "CSAFPID-8862648", "CSAFPID-8862650", "CSAFPID-8862652", "CSAFPID-8873350", "CSAFPID-8873351", "CSAFPID-8873352", "CSAFPID-8585084", "CSAFPID-8585085", "CSAFPID-8585086", "CSAFPID-8585087", "CSAFPID-8585088", "CSAFPID-8585089", "CSAFPID-8585090", "CSAFPID-8585091", "CSAFPID-8585092", "CSAFPID-8585093", "CSAFPID-8585094", "CSAFPID-8678078", "CSAFPID-8678079", "CSAFPID-8895578", "CSAFPID-8895579", "CSAFPID-8895580", "CSAFPID-8895581", "CSAFPID-8895582", "CSAFPID-6619736", "CSAFPID-6619737", "CSAFPID-6619738", "CSAFPID-6619739", "CSAFPID-6619740", "CSAFPID-6619741", "CSAFPID-6619742", "CSAFPID-6619743", "CSAFPID-6619744", "CSAFPID-6619745", "CSAFPID-7765514", "CSAFPID-7765515", "CSAFPID-7765516", "CSAFPID-7765517", "CSAFPID-8938719", "CSAFPID-8938720", "CSAFPID-8938721", "CSAFPID-9012403", "CSAFPID-9012404", "CSAFPID-9012405", "CSAFPID-9012406", "CSAFPID-9012407", "CSAFPID-9012408", "CSAFPID-9012409", "CSAFPID-9012410", "CSAFPID-9012411", "CSAFPID-9012413", "CSAFPID-9012414" ], "known_not_affected": [ "CSAFPID-8862649", "CSAFPID-8862651", "CSAFPID-8862653", "CSAFPID-7469275", "CSAFPID-8757775" ] }, "references": [ { "category": "external", "summary": "Source - ncscclear", "url": "https://advisories.ncsc.nl/advisory?id=NCSC-2026-0325" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-16221" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/16xxx/CVE-2026-16221.json" }, { "category": "external", "summary": "Source - debian", "url": "https://security-tracker.debian.org/tracker/CVE-2026-16221" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=20000" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/npm%2FGHSA-v2hh-gcrm-f6hx.json?alt=media" }, { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-v2hh-gcrm-f6hx" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=30000" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/GIT%2FCVE-2026-16221.json?alt=media" }, { "category": "external", "summary": "Source - osv", "url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Ubuntu%2FUBUNTU-CVE-2026-16221.json?alt=media" }, { "category": "external", "summary": "Source - certbundde", "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2923.json" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=40000" }, { "category": "external", "summary": "Source - ncscclear", "url": "https://vulnerabilities.ncsc.nl/manual/CVE-2026-16221" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd; osv", "url": "https://github.com/fastify/fast-uri/security/advisories/GHSA-v2hh-gcrm-f6hx" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd; osv", "url": "https://cna.openjsf.org/security-advisories.html" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16221" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/commit/0542a216860fd70c062a4730e620576f62ded057" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/commit/2d50fbabc80e4d0884fe0f6a98fe118ce6faa353" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/commit/9438266d6a7ded688c8bc7c4ba506da17f44a17b" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/releases/tag/v2.4.3" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/releases/tag/v3.1.4" }, { "category": "external", "summary": "Reference - github; osv", "url": "https://github.com/fastify/fast-uri/releases/tag/v4.1.1" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-v2hh-gcrm-f6hx" }, { "category": "external", "summary": "Reference - osv", "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16221.json" }, { "category": "external", "summary": "Reference - osv", "url": "https://ubuntu.com/security/CVE-2026-16221" }, { "category": "external", "summary": "Reference - osv", "url": "https://www.cve.org/CVERecord?id=CVE-2026-16221" }, { "category": "external", "summary": "Reference - certbundde", "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2923.json" }, { "category": "external", "summary": "Reference - certbundde", "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2923" }, { "category": "external", "summary": "Reference - certbundde", "url": "https://confluence.atlassian.com/security/security-bulletin-august-18-2026-1821999768.html" } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "baseScore": 7.5, "baseSeverity": "HIGH" }, "products": [ "CSAFPID-6619736", "CSAFPID-6619737", "CSAFPID-6619738", "CSAFPID-6619739", "CSAFPID-6619740", "CSAFPID-6619741", "CSAFPID-6619742", "CSAFPID-6619743", "CSAFPID-6619744", "CSAFPID-6619745", "CSAFPID-7765514", "CSAFPID-7765515", "CSAFPID-7765516", "CSAFPID-7765517", "CSAFPID-8585084", "CSAFPID-8585085", "CSAFPID-8585086", "CSAFPID-8585087", "CSAFPID-8585088", "CSAFPID-8585089", "CSAFPID-8585090", "CSAFPID-8585091", "CSAFPID-8585092", "CSAFPID-8585093", "CSAFPID-8585094", "CSAFPID-8678078", "CSAFPID-8678079", "CSAFPID-8862648", "CSAFPID-8862650", "CSAFPID-8862652", "CSAFPID-8873350", "CSAFPID-8873351", "CSAFPID-8873352", "CSAFPID-8895578", "CSAFPID-8895579", "CSAFPID-8895580", "CSAFPID-8895581", "CSAFPID-8895582", "CSAFPID-8938719", "CSAFPID-8938720", "CSAFPID-8938721", "CSAFPID-9012403", "CSAFPID-9012404", "CSAFPID-9012405", "CSAFPID-9012406", "CSAFPID-9012407", "CSAFPID-9012408", "CSAFPID-9012409", "CSAFPID-9012410", "CSAFPID-9012411", "CSAFPID-9012413", "CSAFPID-9012414" ] } ], "title": "CVE-2026-16221" } ] }