# CVE-2026-42206: Roadiz OpenID Connect nonce generated but never validated — ID token replay attack

> Attackers can replay OpenID Connect ID tokens to bypass authentication and take over user accounts due to missing nonce validation.

- **Severity:** Medium 5.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 May 2026
- **Updated:** 13 May 2026
- **Also known as:** GHSA-3gx8-q682-38mx

## What is CVE-2026-42206?

CVE-2026-42206 is a medium-severity authentication bypass vulnerability in roadiz core-bundle-dev-app, published on 8 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Roadiz is a polymorphic content management system based on a node system. Prior to versions 2.3.43, 2.5.45, 2.6.31, and 2.7.18, the roadiz/openid package generates an OIDC nonce in OAuth2LinkGenerator::generate() and includes it in the authorization request sent to the identity provider, but never stores it and never validates it on the callback. The OpenIdJwtConfigurationFactory validation chain does not include a nonce constraint, and OpenIdAuthenticator::authenticate() never checks the nonce claim in the returned ID token against a stored value. This issue has been patched in versions 2.3.43, 2.5.45, 2.6.31, and 2.7.18.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity)

## Which versions are affected by CVE-2026-42206?

8 open source packages ship an affected version, including roadiz/openid.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `roadiz/openid` | Packagist | All versions | 2.3.43 |
| `roadiz/openid` | Packagist | All versions | 2.3.43 |
| `roadiz/openid` | Packagist | From 2.5.0 | 2.5.45 |
| `roadiz/openid` | Packagist | From 2.5.0 | 2.5.45 |
| `roadiz/openid` | Packagist | From 2.6.0 | 2.6.31 |
| `roadiz/openid` | Packagist | From 2.6.0 | 2.6.31 |
| `roadiz/openid` | Packagist | From 2.7.0 | 2.7.18 |
| `roadiz/openid` | Packagist | From 2.7.0 | 2.7.18 |

## How do I fix CVE-2026-42206?

Upgrade roadiz/openid to a fixed version for your release line: 2.3.43, 2.5.45, 2.6.31 or 2.7.18.

## Is CVE-2026-42206 being exploited?

There is no known exploitation of CVE-2026-42206 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-42206 and fix it if it is affected.

What it is: CVE-2026-42206 is a medium-severity authentication bypass vulnerability in roadiz core-bundle-dev-app, published on 8 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-42206 in the wild and no public exploit code.

Affected packages and fixed versions:
- roadiz/openid (Packagist): affected all versions; fixed in 2.3.43
- roadiz/openid (Packagist): affected all versions; fixed in 2.3.43
- roadiz/openid (Packagist): affected from 2.5.0; fixed in 2.5.45
- roadiz/openid (Packagist): affected from 2.5.0; fixed in 2.5.45
- roadiz/openid (Packagist): affected from 2.6.0; fixed in 2.6.31
- roadiz/openid (Packagist): affected from 2.6.0; fixed in 2.6.31
- roadiz/openid (Packagist): affected from 2.7.0; fixed in 2.7.18
- roadiz/openid (Packagist): affected from 2.7.0; fixed in 2.7.18

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-42206/ (Markdown: https://insights.sbomify.com/CVE-2026-42206/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42206
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42206
- OSV: https://osv.dev/vulnerability/CVE-2026-42206

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-42206/
Summaries are generated and may contain mistakes; the official description above is the record.