How severe is CVE-2019-17557?

CVE-2019-17557 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2019-17557?

CVE-2019-17557 affects the following packages: org.apache.syncope.client:syncope-client-enduser (Maven), org.apache.syncope.client:syncope-client-enduser (Maven). Ecosystems affected: Maven.

How do I fix CVE-2019-17557?

Update org.apache.syncope.client:syncope-client-enduser to 2.0.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-17557 is resolved across your whole dependency graph.

How do I detect CVE-2019-17557 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.syncope.client:syncope-client-enduser, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2019-17557 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2019-17557 actively exploited in the wild?

No public exploit code has been indexed for CVE-2019-17557 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2019-17557?

CVE-2019-17557 has an EPSS (Exploit Prediction Scoring System) score of 1.2%, placing it in the 68th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2019-17557?

CVE-2019-17557 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2019-17557 published, and has it been updated?

CVE-2019-17557 was published on May 4, 2020 and was last updated on July 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2019-17557 — syncope-client-enduser

MEDIUM

CVE-2019-17557 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in org.apache.syncope.client:syncope-client-enduser. A fix is available for org.apache.syncope.client:syncope-client-enduser — see the affected versions and patch details below.

Cross-site scripting in Apache Syncome EndUser

Also known asGHSA-6qj8-c27w-rp33

Published

May 4, 2020

Updated

Jul 8, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

1.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs68th percentile — riskier than 68% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2019-17557 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

☕org.apache.syncope.client:syncope-client-enduser☕org.apache.syncope.client:syncope-client-enduser

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

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.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.syncope.client:syncope-client-enduser`	all versions	2.0.15`org.apache.syncope.client:syncope-client-enduser:2.0.15`
☕Maven	`org.apache.syncope.client:syncope-client-enduser`	≥ 2.1.0&&< 2.1.6	2.1.6`org.apache.syncope.client:syncope-client-enduser:2.1.6`

Affected Products

1 product · 2 configurations

Application

syncopeapache

≥ 2.1.0 && < 2.1.6

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.syncope.client:syncope-client-enduser, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.syncope.client:syncope-client-enduser to 2.0.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-17557 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2019-17557 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.4/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No known public exploit tooling found.

Timeline

Disclosed

May 4, 2020

Last updated

Jul 8, 2026

Identifiers

CVE-2019-17557

GHSA-6qj8-c27w-rp33

References

Advisorysyncope.apache.org Advisorynvd.nist.gov

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-79 are rated as high or higher (top: high).

CVE-2026-91127CVE-2026-77606CVE-2026-84992CVE-2026-77608CVE-2026-77607GHSA-9rcc-pmj8-ffhrCVE-2026-77616CVE-2025-61682Browse all CWE-79

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedJul 8, 2026