GHSA-GPXG-FX2G-QXJ2

The 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.

Details

• https://github.com/kanidm/kanidm/blob/master/server/core/templates/credential_update_add_passkey_partial.html#L3, the |safe sink
• https://github.com/kanidm/kanidm/blob/master/server/core/src/https/views/reset.rs#L506-L509, serde_json::to_string of the challenge
• https://github.com/kanidm/kanidm/blob/master/server/lib/src/idm/credupdatesession.rs#L2453-L2460, displayname flows into start_passkey_registration

Affected versions

All releases shipping the htmx credential-update views

An 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.

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

GHSA-GPXG-FX2G-QXJ2 has a CVSS score of 6.1 (Medium). The vector is network-reachable, high privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.9.3); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is GHSA-GPXG-FX2G-QXJ2? GHSA-GPXG-FX2G-QXJ2 is a medium-severity cross-site scripting (XSS) vulnerability in kanidm (rust), affecting versions <= 1.9.2. It is fixed in 1.9.3. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is GHSA-GPXG-FX2G-QXJ2? GHSA-GPXG-FX2G-QXJ2 has a CVSS score of 6.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of kanidm are affected by GHSA-GPXG-FX2G-QXJ2? kanidm (rust) versions <= 1.9.2 is affected.
4. Is there a fix for GHSA-GPXG-FX2G-QXJ2? Yes. GHSA-GPXG-FX2G-QXJ2 is fixed in 1.9.3. Upgrade to this version or later.
5. Is GHSA-GPXG-FX2G-QXJ2 exploitable, and should I be worried? Whether GHSA-GPXG-FX2G-QXJ2 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether GHSA-GPXG-FX2G-QXJ2 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix GHSA-GPXG-FX2G-QXJ2? Upgrade kanidm to 1.9.3 or later.