# CVE-2020-1727: Open redirect in keycloak

> Attackers can craft malicious deep links due to insufficient input validation in Keycloak's IDP authorization URLs, potentially redirecting users to malicious sites.

- **Severity:** Medium 6.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Jun 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-pw23-237p-qf6r

## What is CVE-2020-1727?

CVE-2020-1727 is a medium-severity vulnerability in Redhat Keycloak, published on 22 Jun 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was found in Keycloak before 9.0.2, where every Authorization URL that points to an IDP server lacks proper input validation as it allows a wide range of characters. This flaw allows a malicious to craft deep links that introduce further attack scenarios on affected clients.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2020-1727?

It affects 1 product.


Products: Redhat Keycloak.

## How do I fix CVE-2020-1727?

No fix has been published for CVE-2020-1727 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-1727 being exploited?

There is no known exploitation of CVE-2020-1727 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Keycloak

- [CVE-2022-4361](https://insights.sbomify.com/CVE-2022-4361/): Keycloak vulnerable to cross-site scripting when validating URI-schemes on SAML and OIDC (critical 10.0)
- [CVE-2022-1245](https://insights.sbomify.com/CVE-2022-1245/): Keycloak vulnerable to privilege escalation on Token Exchange feature (critical 9.8)
- [CVE-2021-20195](https://insights.sbomify.com/CVE-2021-20195/): keycloak Self Stored Cross-site Scripting vulnerability (critical 9.6)
- [CVE-2019-14910](https://insights.sbomify.com/CVE-2019-14910/): Keycloak Authentication Error (critical 9.3)
- [CVE-2019-14909](https://insights.sbomify.com/CVE-2019-14909/): Keycloak Authentication Error (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-1727 and fix it if it is affected.

What it is: CVE-2020-1727 is a medium-severity vulnerability in Redhat Keycloak, published on 22 Jun 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-1727 in the wild and no public exploit code.

Affected product: Redhat Keycloak. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2020-1727/ (Markdown: https://insights.sbomify.com/CVE-2020-1727/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-1727
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-1727
- OSV: https://osv.dev/vulnerability/CVE-2020-1727

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-1727/
Summaries are generated and may contain mistakes; the official description above is the record.