{"id":"CVE-2021-20777","aliases":["EUVD-2021-8189","GHSA-q6p4-2q7c-4vw7"],"status":"published","title":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android...","description":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.","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":"2026-11-12","score":0.00869,"percentile":0.59245,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-862","CWE-863"],"published":"2021-07-07T07:05:29Z","modified":"2026-06-17T03:34:26Z","products":[{"vendor":"g.u. co., ltd.","product":"gu app for android"},{"vendor":"gu-global","product":"gu"}],"references":[{"url":"https://jvn.jp/en/jp/JVN25850723/index.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20777"},{"url":"https://github.com/advisories/GHSA-q6p4-2q7c-4vw7"}],"sources":{"cve":[{"id":"CVE-2021-20777","description":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.","status":"published","published":"2021-07-07T07:05:29Z","modified":"2024-08-03T17:53:22.082Z","updated_at":"2026-11-02T14:32:55.905855Z"}],"euvd":[{"id":"EUVD-2021-8189","description":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.","status":"published","published":"2021-07-07T07:05:29Z","modified":"2024-08-03T17:53:22Z","updated_at":"2026-11-03T03:25:07.874589Z"}],"ghsa":[{"id":"GHSA-q6p4-2q7c-4vw7","title":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android...","description":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.","status":"published","published":"2022-05-24T19:07:09Z","modified":"2023-01-30T05:00:38Z","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-862","CWE-863"],"updated_at":"2026-11-02T14:46:14.926249Z"}],"nvd":[{"id":"CVE-2021-20777","description":"Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.","status":"published","published":"2021-07-07T08:15:07.887Z","modified":"2026-06-17T03:34:26.153Z","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":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:06:55.259633Z"}]}}