high · 8.3 Patched

OpenAM has pre-auth Reflected XSS in OAuth2 / OIDC response_mode=form_post via state parameter (FormPostResponse.ftl)

CVE-2026-44203 · GHSA-fq9h-c788-fx73 · published 22 Jun 2026

How serious is it

  • Severity: high, CVSS score 8.3 out of 10.
  • No exploit prediction (EPSS) score yet.
  • Not on the CISA list of exploited vulnerabilities.
  • No public exploit in Exploit-DB.

Is your app affected by CVE-2026-44203?

Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.

Who is affected

  • org.openidentityplatform.openam:openam-oauth2 (Maven) >= 13.0.0, < 16.1.1

How to check

  1. Look for org.openidentityplatform.openam:openam-oauth2 in your lockfile and compare its version with the range above.
  2. Or paste your lockfile into the checker: it lists every package with a known vulnerability, this one included.

How to fix

Copies a prompt for Claude Code, Cursor or Codex: it checks your lockfiles for this and upgrades it.
  1. Upgrade org.openidentityplatform.openam:openam-oauth2 to 16.1.1 or later, commit the lockfile and redeploy.
  2. If a vulnerable version was live, check your logs and rotate the secrets that server could read.

The advisory

### Summary The OAuth 2.0 / OpenID Connect authorization endpoint does not sufficiently sanitize certain user-supplied parameters before incorporating them into the HTML response generated for the `form_post` response mode. This may allow an attacker to inject content into the rendered page in the context of the OpenAM origin.

Check your whole app

Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.

References

Merged from GitHub Advisory Database, OSV. Last updated 29 Oct 2026. All vulnerabilities · RSS · JSON

Get alerts for new exploited vulnerabilities