# CVE-2026-16089: Keycloak-services: keycloak-services: authorization codes can be retargeted to another client session

> Attackers can intercept and retarget OAuth authorization codes to their own client, potentially obtaining access tokens for victim identities.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 17 Jul 2026
- **Updated:** 16 Sep 2026
- **Also known as:** BIT-keycloak-2026-16089, CLEANSTART-2026-QJ88718, GHSA-63wm-fvw8-h2hp

## What is CVE-2026-16089?

CVE-2026-16089 is a medium-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 17 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

A flaw was found in the keycloak-services component of Red Hat Build of Keycloak. The issue occurs because OAuth 2.0 authorization codes are not properly bound to the client that originally requested them. An attacker who can intercept an authorization code can modify it to be redeemed by their own client, potentially allowing them to obtain access tokens for a victim's identity.

Weakness: CWE-384 (Session Fixation), CWE-472 (External Control of Assumed-Immutable Web Parameter)

## Which versions are affected by CVE-2026-16089?

1 open source package ship an affected version, including keycloak. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `keycloak` | Bitnami | All versions | 26.7.3 |

Products: Redhat Build of Keycloak.

## How do I fix CVE-2026-16089?

Upgrade keycloak to 26.7.3 or later.

## Is CVE-2026-16089 being exploited?

There is no known exploitation of CVE-2026-16089 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Build of Keycloak

- [CVE-2026-15572](https://insights.sbomify.com/CVE-2026-15572/): Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation (high 8.8)
- [CVE-2026-3047](https://insights.sbomify.com/CVE-2026-3047/): Keycloak SAML Broken has Authentication Bypass by Primary Weakness (high 8.8)
- [CVE-2026-15573](https://insights.sbomify.com/CVE-2026-15573/): Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher (high 8.1)
- [CVE-2026-16102](https://insights.sbomify.com/CVE-2026-16102/): Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers (high 8.1)
- [CVE-2026-1609](https://insights.sbomify.com/CVE-2026-1609/): Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-16089 and fix it if it is affected.

What it is: CVE-2026-16089 is a medium-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 17 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-16089 in the wild and no public exploit code.

Affected packages and fixed versions:
- keycloak (Bitnami): affected all versions; fixed in 26.7.3

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-2026-16089/ (Markdown: https://insights.sbomify.com/CVE-2026-16089/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-16089
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-16089
- OSV: https://osv.dev/vulnerability/CVE-2026-16089

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-16089/
Summaries are generated and may contain mistakes; the official description above is the record.