{"id":"CVE-2021-32702","aliases":["EUVD-2021-1297","GHSA-954c-jjx6-cxv7"],"status":"published","title":"Reflected XSS from the callback handler's error query parameter","description":"The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.","severity":{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.01397,"percentile":0.7278,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-79"],"published":"2021-06-25T16:25:11Z","modified":"2026-10-20T10:54:43Z","fixes":[{"ecosystem":"npm","package":"@auth0/nextjs-auth0","fixed_in":["1.4.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"@auth0/nextjs-auth0","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2"}]}]},{"source":"osv","ecosystem":"npm","package":"@auth0/nextjs-auth0","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.4.2"}]}]}],"products":[{"vendor":"auth0","product":"nextjs-auth0"}],"references":[{"url":"https://github.com/auth0/nextjs-auth0/security/advisories/GHSA-954c-jjx6-cxv7","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://github.com/auth0/nextjs-auth0/commit/6996e2528ceed98627caa28abafbc09e90163ccf","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://www.npmjs.com/package/%40auth0/nextjs-auth0","tags":["x_refsource_MISC","x_transferred","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32702","tags":["advisory"]},{"url":"https://www.npmjs.com/package/@auth0/nextjs-auth0","tags":["web"]},{"url":"https://github.com/advisories/GHSA-954c-jjx6-cxv7"}],"sources":{"cve":[{"id":"CVE-2021-32702","title":"Reflected XSS from the callback handler's error query parameter","description":"The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.","status":"published","published":"2021-06-25T16:25:11Z","modified":"2024-08-03T23:25:31.131Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:33:07.014772Z"}],"euvd":[{"id":"EUVD-2021-1297","description":"The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.","status":"published","published":"2021-06-25T16:25:11Z","modified":"2024-08-03T23:25:31Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:24:36.41075Z"}],"ghsa":[{"id":"GHSA-954c-jjx6-cxv7","title":"Reflected XSS from the callback handler's error query parameter","description":"### Overview\n\nVersions before and including `1.4.1` are vulnerable to reflected XSS.  An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message.\n\n### Am I affected?\nYou are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response.\n\n### How to fix that?\nUpgrade to version `1.4.2`.\n\n### Will this update impact my users?\nThe fix adds basic HTML escaping to the error message and it should not impact your users.\n\n### Credit\n\nhttps://github.com/inian\nhttps://github.com/git-ishanpatel","status":"published","published":"2021-06-28T16:46:41Z","modified":"2023-02-01T05:05:52Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:36:35.781528Z"}],"nvd":[{"id":"CVE-2021-32702","description":"The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.","status":"published","published":"2021-06-25T17:15:08.383Z","modified":"2026-06-17T03:53:27.48Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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-79"],"updated_at":"2026-11-02T14:06:54.892562Z"}],"osv":[{"id":"CVE-2021-32702","description":"The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.","status":"published","published":"2021-06-25T17:15:08.383Z","modified":"2026-10-20T10:54:43.866056467Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:19.793849Z"},{"id":"GHSA-954c-jjx6-cxv7","title":"Reflected XSS from the callback handler's error query parameter","description":"### Overview\n\nVersions before and including `1.4.1` are vulnerable to reflected XSS.  An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message.\n\n### Am I affected?\nYou are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response.\n\n### How to fix that?\nUpgrade to version `1.4.2`.\n\n### Will this update impact my users?\nThe fix adds basic HTML escaping to the error message and it should not impact your users.\n\n### Credit\n\nhttps://github.com/inian\nhttps://github.com/git-ishanpatel","status":"published","published":"2021-06-28T16:46:41Z","modified":"2026-07-08T06:29:07.810465813Z","cvss":[{"version":"3.1","score":8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:46:43.123867Z"}]}}