{"items":[{"id":"NVI-00010552","kind":"vulnerability","title":"fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding","revision":4,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-w74x-v6f9-j3xg","CVE-2026-110306"],"plain_summary":"GitHub lists this reviewed advisory for fast-uri, fast-uri, fast-uri. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-10bf5485a017a21c488e6e3fb57ddcc5"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 2.4.8 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 3.1.9 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 4.2.3 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-23T21:41:38.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-3837970968f579237b1853ed26c97224"},{"kind":"EPSS","as_of":"2026-11-03T12:00:27.000Z","value":"0.250%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.1638. Missing scores are unknown.","source_id":"sr-10bf5485a017a21c488e6e3fb57ddcc5"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-3837970968f579237b1853ed26c97224","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"},{"id":"sr-3ca753ca179c6ed51bce1b75e45c453f","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-11-04T23:34:34.031Z"},{"id":"sr-10bf5485a017a21c488e6e3fb57ddcc5","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-110306","publisher":"FIRST EPSS","observed_at":"2026-11-03T17:44:07.775Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["< 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 3.0.0, < 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 4.0.0, < 4.2.3"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 0; fixed 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 3.0.0; fixed 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 4.0.0; fixed 4.2.3"]}],"null_published_at":"2026-11-06T00:29:57.292Z","source_updated_at":"2026-10-23T21:41:38.000Z","source_disclosed_at":"2026-10-23T21:41:36.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T22:07:08.657Z"},{"id":"NVI-00010552","kind":"vulnerability","title":"fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-w74x-v6f9-j3xg","CVE-2026-110306"],"plain_summary":"GitHub lists this reviewed advisory for fast-uri, fast-uri, fast-uri. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-1b619825252ea21bc0c758636e07b132"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 2.4.8 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 3.1.9 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null},{"summary":"The original advisory lists fixed boundaries 4.2.3 for fast-uri. Confirm the publisher’s latest guidance.","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"action_type":"vendor_patch","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-23T21:41:38.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-3837970968f579237b1853ed26c97224"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.250%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.16356. Missing scores are unknown.","source_id":"sr-1b619825252ea21bc0c758636e07b132"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-3837970968f579237b1853ed26c97224","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"},{"id":"sr-3ca753ca179c6ed51bce1b75e45c453f","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database via OSV","observed_at":"2026-11-04T23:34:34.031Z"},{"id":"sr-1b619825252ea21bc0c758636e07b132","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-110306","publisher":"FIRST EPSS","observed_at":"2026-10-31T23:13:27.688Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["< 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 3.0.0, < 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 4.0.0, < 4.2.3"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 0; fixed 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 3.0.0; fixed 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3ca753ca179c6ed51bce1b75e45c453f"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["SEMVER: introduced 4.0.0; fixed 4.2.3"]}],"null_published_at":"2026-11-05T03:52:54.734Z","source_updated_at":"2026-10-23T21:41:38.000Z","source_disclosed_at":"2026-10-23T21:41:36.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T22:07:08.657Z"},{"id":"NVI-00010552","kind":"vulnerability","title":"fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-w74x-v6f9-j3xg","CVE-2026-110306"],"plain_summary":"GitHub lists this reviewed advisory for fast-uri, fast-uri, fast-uri. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-1b619825252ea21bc0c758636e07b132"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-23T21:41:38.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-3837970968f579237b1853ed26c97224"},{"kind":"EPSS","as_of":"2026-10-31T12:00:27.000Z","value":"0.250%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.16356. Missing scores are unknown.","source_id":"sr-1b619825252ea21bc0c758636e07b132"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-3837970968f579237b1853ed26c97224","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"},{"id":"sr-1b619825252ea21bc0c758636e07b132","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-110306","publisher":"FIRST EPSS","observed_at":"2026-10-31T23:13:27.688Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["< 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 3.0.0, < 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 4.0.0, < 4.2.3"]}],"null_published_at":"2026-10-31T23:18:22.441Z","source_updated_at":"2026-10-23T21:41:38.000Z","source_disclosed_at":"2026-10-23T21:41:36.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T22:07:08.657Z"},{"id":"NVI-00010552","kind":"vulnerability","title":"fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-w74x-v6f9-j3xg","CVE-2026-110306"],"plain_summary":"GitHub lists this reviewed advisory for fast-uri, fast-uri, fast-uri. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-3837970968f579237b1853ed26c97224"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-23T21:41:38.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-3837970968f579237b1853ed26c97224"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-3837970968f579237b1853ed26c97224","url":"https://github.com/advisories/GHSA-w74x-v6f9-j3xg","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-w74x-v6f9-j3xg","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T22:07:08.657Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":["< 2.4.8"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 3.0.0, < 3.1.9"]},{"certainty":"source_listed","source_ids":["sr-3837970968f579237b1853ed26c97224"],"technology":"fast-uri","known_exclusions":[],"conditions_summary":"### Impact\n\n`fast-uri` percent-decodes the scheme component with the legacy global `unescape()` before validating it, so an input whose decoded scheme is a valid but dangerous token is emitted as a live scheme. RFC 3986 section 3.1 does not allow percent-encoding in a scheme, so no RFC or WHATWG parser treats such input as having that scheme, but `fast-uri` does.\n\nFor example, `normalize('%6Aavascript:alert(1)')` returns `javascript:alert(1)`, `resolve('https://a.example/', '%6Aavascript:alert(1)')` returns `javascript:alert(1)`, and `parse('%6Aavascript:alert(1)').scheme` returns `javascript`. The `%uXXXX` form (`%u006Aavascript:`) produces the same result, and `equal('%68ttp://a/', 'http://a/')` returns `true`.\n\nAn application that screens dangerous schemes on the raw input and then stores or renders `normalize(input)` or `resolve(base, input)` turns an inert string into an executable `javascript:`, `data:`, or `vbscript:` URL, a stored or reflected cross-site scripting vector in the consuming application. `equal()` also treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n","public_affected_ranges":[">= 4.0.0, < 4.2.3"]}],"null_published_at":"2026-10-31T22:27:09.621Z","source_updated_at":"2026-10-23T21:41:38.000Z","source_disclosed_at":"2026-10-23T21:41:36.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T22:07:08.657Z"}],"next_cursor":null,"snapshot_revision":"42594"}