# CVE-2019-17557: Cross-site scripting in Apache Syncome EndUser

> Attackers can execute arbitrary JavaScript in the Apache Syncope EndUser UI via the successMessage parameter, potentially compromising user sessions.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 May 2020
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-6qj8-c27w-rp33

## What is CVE-2019-17557?

CVE-2019-17557 is a medium-severity cross-site scripting vulnerability in Apache Syncope, published on 4 May 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

It was found that the Apache Syncope EndUser UI login page prio to 2.0.15 and 2.1.6 reflects the successMessage parameters. By this mean, a user accessing the Enduser UI could execute javascript code from URL query string.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2019-17557?

4 open source packages ship an affected version, including org.apache.syncope.client:syncope-client-enduser. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.syncope.client:syncope-client-enduser` | Maven | All versions | 2.0.15 |
| `org.apache.syncope.client:syncope-client-enduser` | Maven | All versions | 2.0.15 |
| `org.apache.syncope.client:syncope-client-enduser` | Maven | From 2.1.0 | 2.1.6 |
| `org.apache.syncope.client:syncope-client-enduser` | Maven | From 2.1.0 | 2.1.6 |

Products: Apache Syncope.

## How do I fix CVE-2019-17557?

Upgrade org.apache.syncope.client:syncope-client-enduser to a fixed version for your release line: 2.0.15 or 2.1.6.

## Is CVE-2019-17557 being exploited?

There is no known exploitation of CVE-2019-17557 in the wild and no public exploit code.

## Other vulnerabilities in Apache Syncope

- [CVE-2026-53405](https://insights.sbomify.com/CVE-2026-53405/): Apache Syncope: Remote Code Execution via Flowable BPMN Groovy ScriptTask (critical 9.8)
- [CVE-2026-53421](https://insights.sbomify.com/CVE-2026-53421/): Apache Syncope: Remote Code Execution via Scripted Connector (critical 9.8)
- [CVE-2026-57308](https://insights.sbomify.com/CVE-2026-57308/): Apache Syncope: SQL injection vulnerability in Audit Events search (critical 9.8)
- [CVE-2026-62183](https://insights.sbomify.com/CVE-2026-62183/): Apache Syncope: User self-service privilege escalation (critical 9.8)
- [CVE-2026-63071](https://insights.sbomify.com/CVE-2026-63071/): Apache Syncope: RCE via Groovy Sandbox bypass (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-17557 and fix it if it is affected.

What it is: CVE-2019-17557 is a medium-severity cross-site scripting vulnerability in Apache Syncope, published on 4 May 2020. 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-2019-17557 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.syncope.client:syncope-client-enduser (Maven): affected all versions; fixed in 2.0.15
- org.apache.syncope.client:syncope-client-enduser (Maven): affected all versions; fixed in 2.0.15
- org.apache.syncope.client:syncope-client-enduser (Maven): affected from 2.1.0; fixed in 2.1.6
- org.apache.syncope.client:syncope-client-enduser (Maven): affected from 2.1.0; fixed in 2.1.6

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-2019-17557/ (Markdown: https://insights.sbomify.com/CVE-2019-17557/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-17557
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-17557
- OSV: https://osv.dev/vulnerability/CVE-2019-17557

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-17557/
Summaries are generated and may contain mistakes; the official description above is the record.