GHSA-gpxg-fx2g-qxj2: Kanidm Stored HTML Injection Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-gpxg-fx2g-qxj2",
  "modified" : "2026-05-06T23:34:20Z",
  "published" : "2026-05-06T23:34:20Z",
  "aliases" : [ ],
  "summary" : "Kanidm: Stored HTML injection in \"passkey-enrolment\" partial via displayname → htmx-driven authenticated request forgery",
  "details" : "### Summary\n\nThe kanidmd web UI renders the WebAuthn passkey-registration challenge as raw JSON inside an inline `<script id=\"data\">` element using the Askama `|safe` filter. The challenge embeds the account's `displayname`, which `serde_json` serialises without escaping `<`/`>`. A `displayname` containing `</script>` therefore terminates the script element early and injects arbitrary HTML into the credential-update page. Because the page is htmx-driven and the server's CSP allows `'unsafe-eval'`, injected `hx-*` attributes can issue authenticated same-origin API requests with the viewer's bearer cookie.\n\n### Impact\n\nAn authenticated attacker who is a member of `idm_people_admins` can write the `displayname` of any `Person` entry — including high-privilege persons — because `idm_acp_people_pii_manage` carries no high-privilege exclusion filter. When the targeted high-privilege user later opens **Add Passkey** on their own credential-update page (`/ui/reset`), the injected markup is swapped into the DOM and htmx fires attacker-chosen same-origin requests authenticated as the victim. This allows a helpdesk-tier operator to escalate to `idm_admins` (e.g. by POSTing themselves into the group) or otherwise act with the victim's session. The self-write path (`idm_people_self_name_write`) is self-XSS only and is not counted toward impact. Even without the htmx vector, the breakout permits `<meta http-equiv='refresh'>` open-redirect and arbitrary defacement of the credential page.\n\n### Details\n\n- https://github.com/kanidm/kanidm/blob/master/server/core/templates/credential_update_add_passkey_partial.html#L3 — the `|safe` sink\n- https://github.com/kanidm/kanidm/blob/master/server/core/src/https/views/reset.rs#L506-L509 — `serde_json::to_string` of the challenge\n- https://github.com/kanidm/kanidm/blob/master/server/lib/src/idm/credupdatesession.rs#L2453-L2460 — `displayname` flows into `start_passkey_registration`\n\n### Affected versions\n\nAll releases shipping the htmx credential-update views",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "kanidm"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.9.3"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 1.9.2"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/kanidm/kanidm/security/advisories/GHSA-gpxg-fx2g-qxj2"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/kanidm/kanidm"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T23:34:20Z",
    "nvd_published_at" : null
  }
}