{"id":"CVE-2021-4221","aliases":["EUVD-2021-34079","GHSA-wmph-fgw4-55rj"],"status":"published","title":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right...","description":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. \u003cbr\u003e*This bug only affects Firefox for Android. Other operating systems are unaffected.*\u003cbr\u003e*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox \u003c 92.","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.0043,"percentile":0.37675,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-1007"],"published":"2022-12-22T00:00:00Z","modified":"2026-06-17T04:19:14Z","products":[{"vendor":"mozilla","product":"firefox"}],"references":[{"url":"https://www.mozilla.org/security/advisories/mfsa2021-38/","tags":["x_transferred","Vendor Advisory"]},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1704422","tags":["x_transferred","Exploit","Issue Tracking","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-4221"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-38"},{"url":"https://github.com/advisories/GHSA-wmph-fgw4-55rj"}],"sources":{"cve":[{"id":"CVE-2021-4221","description":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. \u003cbr\u003e*This bug only affects Firefox for Android. Other operating systems are unaffected.*\u003cbr\u003e*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox \u003c 92.","status":"published","published":"2022-12-22T00:00:00Z","modified":"2025-04-16T15:49:45.732Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-1007"],"updated_at":"2026-11-02T14:33:07.697752Z"}],"euvd":[{"id":"EUVD-2021-34079","description":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. \u003cbr\u003e*This bug only affects Firefox for Android. Other operating systems are unaffected.*\u003cbr\u003e*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox \u003c 92.","status":"published","published":"2022-12-22T00:00:00Z","modified":"2025-04-16T15:49:45Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T20:52:24.837818Z"}],"ghsa":[{"id":"GHSA-wmph-fgw4-55rj","title":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right...","description":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. \u003cbr\u003e*This bug only affects Firefox for Android. Other operating systems are unaffected.*\u003cbr\u003e*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox \u003c 92.","status":"published","published":"2022-12-22T21:30:31Z","modified":"2025-04-16T18:31:34Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-1007"],"updated_at":"2026-11-02T15:01:34.863019Z"}],"nvd":[{"id":"CVE-2021-4221","description":"If a domain name contained a RTL character, it would cause the domain to be rendered to the right of the path. This could lead to user confusion and spoofing attacks. \u003cbr\u003e*This bug only affects Firefox for Android. Other operating systems are unaffected.*\u003cbr\u003e*Note*: Due to a clerical error this advisory was not included in the original announcement, and was added in Feburary 2022. This vulnerability affects Firefox \u003c 92.","status":"published","published":"2022-12-22T20:15:12.337Z","modified":"2026-06-17T04:19:14.537Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"},{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-1007"],"updated_at":"2026-11-02T14:07:07.323379Z"}]}}