CVE-2019-25027: Flow server Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-rp4x-wxqv-cf9m
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CVSS 6.1
CWE-81 CWE-79
Published
Advisory Summary

CVE-2019-25027 is a MODERATE (CVSS 6.1) cross-site scripting vulnerability (CWE-81: Improper Neutralization of Script in an Error Message Web Page) affecting Flow server libraries in the Maven ecosystem. The issue involves reflected cross-site scripting in default routenotfounderror view in vaadin 10 and 11-13. Remediation is available by upgrading affected packages to version 1.0.11, 1.4.3.

CVE-2019-25027 at a Glance

CVE Identifier CVE-2019-25027
GHSA Identifier GHSA-rp4x-wxqv-cf9m
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-81: Improper Neutralization of Script in an Error Message Web Page
Affected Product Flow server
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 6.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2019-25027

To remediate this vulnerability, upgrade all affected Flow server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.vaadin:flow-server fixed: 1.0.11 
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>flow-server</artifactId>
    <version>1.0.11</version>
</dependency>
com.vaadin:flow-server fixed: 1.4.3 
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>flow-server</artifactId>
    <version>1.4.3</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=com.vaadin

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2019-25027, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.vaadin

Analyze the terminal output to locate any version of Flow server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.0.11), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.vaadin command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-81: Improper Neutralization of Script in an Error Message Web Page, where the product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters that could be interpreted as web-scripting elements when they are sent to an error page. In Flow server, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Missing output sanitization in default `RouteNotFoundError` view in `com.vaadin:flow-server` versions 1.0.0 through 1.0.10 (Vaadin 10.0.0 through 10.0.13), and 1.1.0 through 1.4.2 (Vaadin 11.0.0 through 13.0.5) allows attacker to execute malicious JavaScript via crafted URL. - https://vaadin.com/security/cve-2019-25027

CVE-2019-25027 Affected Flow server Versions

2 component(s)
Fixed Versions:
1.0.111.4.3
Product / Package Ecosystem Affected Versions Fixed Version
com.vaadin:flow-server
maven/com.vaadin/flow-server
Maven
≥ 1.0.0
< 1.0.11
1.0.11
com.vaadin:flow-server
maven/com.vaadin/flow-server
Maven
≥ 1.1.0
< 1.4.3
1.4.3

References

GitHub Advisory / Wiki ADVISORY
https://github.com/vaadin/flow/security/advisories/GHSA-rp4x-wxqv-cf9m
NVD — CVE-2019-25027 NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-25027
Flow server Source Repository REPOSITORY
https://github.com/vaadin/flow/pull/5498
Flow server Security Information SECURITY
https://vaadin.com/security/cve-2019-25027

Frequently Asked Questions

What is CVE-2019-25027?
CVE-2019-25027 is a security vulnerability in Flow server involving Reflected cross-site scripting in default RouteNotFoundError view in Vaadin 10 and 11-13 under CWE-81: Improper Neutralization of Script in an Error Message Web Page.
Which Flow server versions are affected?
Affected versions include releases prior to 1.0.11, 1.4.3 across affected packages: com.vaadin:flow-server.
What version fixes CVE-2019-25027?
Upgrading to 1.0.11, 1.4.3 (or the latest patched release for your respective branch) resolves the vulnerability.
Is flow-server affected?
Yes, com.vaadin:flow-server is affected in releases prior to 1.0.11, 1.4.3. Upgrade your dependency to 1.0.11, 1.4.3 or later.
What is the CVSS score of CVE-2019-25027?
CVE-2019-25027 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2019-25027?
CVE-2019-25027 is classified under CWE-81: Improper Neutralization of Script in an Error Message Web Page (The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters that could be interpreted as web-scripting elements when they are sent to an error page.).
How can I check Maven dependencies for CVE-2019-25027?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.vaadin'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rp4x-wxqv-cf9m",
  "modified" : "2021-04-16T23:17:25Z",
  "published" : "2021-04-19T14:52:29Z",
  "aliases" : [ "CVE-2019-25027" ],
  "summary" : "Reflected cross-site scripting in default RouteNotFoundError view in Vaadin 10 and 11-13",
  "details" : "Missing output sanitization in default `RouteNotFoundError` view in `com.vaadin:flow-server` versions 1.0.0 through 1.0.10 (Vaadin 10.0.0 through 10.0.13), and 1.1.0 through 1.4.2 (Vaadin 11.0.0 through 13.0.5) allows attacker to execute malicious JavaScript via crafted URL.\n\n- https://vaadin.com/security/cve-2019-25027",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.vaadin:flow-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.0.0"
      }, {
        "fixed" : "1.0.11"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.vaadin:flow-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.1.0"
      }, {
        "fixed" : "1.4.3"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/vaadin/flow/security/advisories/GHSA-rp4x-wxqv-cf9m"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2019-25027"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vaadin/flow/pull/5498"
  }, {
    "type" : "WEB",
    "url" : "https://vaadin.com/security/cve-2019-25027"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79", "CWE-81" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-16T23:17:25Z",
    "nvd_published_at" : "2021-04-23T16:15:00Z"
  }
}