GHSA-gj2h-2fpw-fhv9: @nuxt/ui UAuthForm / UForm SSR Markup Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-gj2h-2fpw-fhv9",
  "modified" : "2026-08-04T21:55:59Z",
  "published" : "2026-07-02T20:16:12Z",
  "aliases" : [ ],
  "summary" : "@nuxt/ui: UAuthForm / UForm SSR markup omits `method`, leaking credentials via GET if submitted before hydration",
  "details" : "### Summary\n\n`UForm` and `UAuthForm` render a server-side `<form>` element with no `method` and no `action` attribute, relying on a hydrated `@submit.prevent` handler to intercept submission. If a user submits the form before Vue hydration has attached the handler (autofill plus Enter on a slow network, JS bundle blocked by CSP or CDN failure, etc.), the browser performs the native default: a `GET` to the current URL with every named field, including `<input type=\"password\">`, serialised into the query string.\n\n### Details\n\n`src/runtime/components/Form.vue` (around the template's `<form>` element) emits:\n\n```vue\n<component\n  :is=\"parentBus ? 'div' : 'form'\"\n  :id=\"formId\"\n  ref=\"formRef\"\n  :class=\"ui({ class: [uiProp?.base, props.class] })\"\n  @submit.prevent=\"onSubmitWrapper\"\n>\n```\n\nNo `method`, no `action`. `@submit.prevent` is the only thing stopping native submission, and it only exists after hydration. `UAuthForm` composes `UForm` and inherits the same shape.\n\nThe SSR snapshot of `UAuthForm` (`test/components/__snapshots__/AuthForm.spec.ts.snap`) shows the rendered markup, with `<input type=\"password\" name=\"password\">` inside a `<form>` that has no `method`.\n\n### Proof of concept\n\nReported by @nimonian:\n\n1. Create a minimal Nuxt app with a `UAuthForm`.\n2. Build for production and visit in a browser with network throttling at 4G or slower.\n3. Enter credentials.\n4. Submit (or let autofill + Enter fire before hydration).\n\nThe URL becomes `/login?email=…&password=…`. Reproducible deterministically in Playwright by triggering submit immediately on `load`.\n\n### Impact\n\nAny application using `UAuthForm` (or `UForm` with credential-shaped fields) as documented. The cleartext password lands in:\n\n- the address bar,\n- `window.history`,\n- the `Referer` header of every same-origin subresource fetched from the resulting URL,\n- access logs of any reverse proxy, CDN, or WAF that records request URLs.\n\n### Patch\n\nDefault the rendered `<form>` to `method=\"post\"` so the pre-hydration fallback submits as POST rather than GET. Vue's `@submit.prevent` still intercepts the hydrated case; the attribute only matters in the race window. Applications that explicitly want native GET submission can opt back in by passing `method=\"get\"`.\n\n### Credit\n\nReported by @nimonian. Originally filed as `GHSA-92g7-2fpq-hmq8` against `nuxt/nuxt`; moved here because the affected code lives in `@nuxt/ui`.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@nuxt/ui"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.8.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/ui/security/advisories/GHSA-gj2h-2fpw-fhv9"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/ui/pull/6512"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/nuxt/ui"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nuxt/ui/releases/tag/v4.8.1"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-200", "CWE-598" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-02T20:16:12Z",
    "nvd_published_at" : null
  }
}