{"cve":"CVE-2020-26291","nvd":{"published":"2020-12-31T00:15:12.327","modified":"2026-06-17T03:08:00.733","status":"Modified","description":"URI.js is a javascript URL mutation library (npm package urijs). In URI.js before version 1.19.4, the hostname can be spoofed by using a backslash (`\\`) character followed by an at (`@`) character. If the hostname is used in security decisions, the decision may be incorrect. Depending on library usage and attacker intent, impacts may include allow/block list bypasses, SSRF attacks, open redirects, or other undesired behavior. For example the URL `https://expected-example.com\\@observed-example.com` will incorrectly return `observed-example.com` if using an affected version. Patched versions correctly return `expected-example.com`. Patched versions match the behavior of other parsers which implement the WHATWG URL specification, including web browsers and Node's built-in URL class. Version 1.19.4 is patched against all known payload variants. Version 1.19.3 has a partial patch but is still vulnerable to a payload variant.]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","score":6.5},"cwes":["CWE-20"],"references":["https://github.com/medialize/URI.js/commit/b02bf037c99ac9316b77ff8bfd840e90becf1155","https://github.com/medialize/URI.js/releases/tag/v1.19.4","https://github.com/medialize/URI.js/security/advisories/GHSA-3329-pjwv-fjpg","https://www.npmjs.com/package/urijs","https://github.com/medialize/URI.js/commit/b02bf037c99ac9316b77ff8bfd840e90becf1155"],"products":["uri.js_project:uri.js"],"source":"nvd","synced_at":"2026-10-19T21:12:09.559580076+00:00"},"epss":{"cve":"CVE-2020-26291","score":0.0171,"percentile":0.77356,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-3329-pjwv-fjpg","url":"https://osv.dev/vulnerability/GHSA-3329-pjwv-fjpg","summary":"Hostname spoofing via backslashes in URL","modified":"2026-07-08T06:00:21.997445441Z","packages":[{"ecosystem":"npm","name":"urijs","purl":"pkg:npm/urijs","ranges":["<1.19.4"],"fixed":["1.19.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}