CVE-2026-8839: Software Security Vulnerability Vulnerability

MODERATE

Advisory Identifier: GHSA-4m8c-59q5-hc8f

CVSS 5.3

Published 2026-06-06

Advisory Summary

CVE-2026-8839 is a MODERATE (CVSS 5.3) security vulnerability vulnerability (CWE-639: Authorization Bypass Through User-Controlled Key) affecting Software libraries in the Maven ecosystem. The weakness occurs when the system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-8839 at a Glance

CVE Identifier CVE-2026-8839

GHSA Identifier GHSA-4m8c-59q5-hc8f

Severity MODERATE

CVSS v3.1 Base Score 5.3

CWE Classification CWE-639: Authorization Bypass Through User-Controlled Key

Affected Product Software

Package Ecosystem Maven

Published Date 2026-06-06

Last Updated 2026-06-06

Security Impact

CVSS: 5.3

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:N/S:U/C:N/I:L/A:N).

Attack Vector Network (AV:N)

Attack Complexity Low (AC:L)

Privileges Required None (PR:N)

User Interaction None (UI:N)

Scope Unchanged (S:U)

Confidentiality None (C:N)

Integrity Low (I:L)

Availability None (A:N)

How to Fix CVE-2026-8839

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

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

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-8839, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

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

Note: The mvn dependency:tree 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-639: Authorization Bypass Through User-Controlled Key, where the system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. In Software, 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

The MapPress Maps for WordPress plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in all versions up to, and including, 2.96.6. This is due to missing ownership verification in the REST API routes registered via `Mappress_Api::rest_api_init()`, where the GET `/wp-json/mapp/v1/maps/{mapid}` endpoint uses `'permission_callback' => '__return_true'` and the write endpoints (POST update, DELETE, PATCH mutate, POST clone, POST empty_trash) only check the generic `edit_posts` capability without confirming that the requester owns the targeted map — a gap that is not compensated at the model layer, as `Mappress_Map::get()`, `save()`, `delete()`, `mutate()`, and `empty_trash()` all operate on any caller-supplied map ID without an ownership check. This makes it possible for unauthenticated attackers to read sensitive map data — including POI titles, addresses, coordinates, and body content — for any map on the site by enumerating map IDs, and for authenticated attackers with Contributor-level access and above to modify, delete, trash/restore, or clone any map regardless of its author.

References

NVD — CVE-2026-8839 NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-8839

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L253

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L268

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L328

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L39

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L50

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L75

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L90

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L239

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L379

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L493

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L550

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L253

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L268

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L328

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L39

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L50

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L75

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L90

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L239

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L379

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L493

plugins.trac.wordpress.org/browser/mappress-go... WEB

https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L550

plugins.trac.wordpress.org/changeset WEB

https://plugins.trac.wordpress.org/changeset?old_path=/mappress-google-maps-for-wordpress/tags/2.96.6&new_path=/mappress-google-maps-for-wordpress/tags/2.97.1

www.wordfence.com/threat-intel/vulner... WEB

https://www.wordfence.com/threat-intel/vulnerabilities/id/9f402aa7-24d6-448b-a1d3-5ee7c90b39bc?source=cve

Frequently Asked Questions

What is CVE-2026-8839?

CVE-2026-8839 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-639: Authorization Bypass Through User-Controlled Key.

Which Software versions are affected?

Affected versions include releases prior to current release patches.

What version fixes CVE-2026-8839?

Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.

What is the CVSS score of CVE-2026-8839?

CVE-2026-8839 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

What CWE is associated with CVE-2026-8839?

CVE-2026-8839 is classified under CWE-639: Authorization Bypass Through User-Controlled Key (The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.).

How can I check Maven dependencies for CVE-2026-8839?

Run the dependency tree command: 'mvn dependency:tree'. 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-4m8c-59q5-hc8f",
  "modified" : "2026-06-06T06:30:29Z",
  "published" : "2026-06-06T06:30:29Z",
  "aliases" : [ "CVE-2026-8839" ],
  "details" : "The MapPress Maps for WordPress plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in all versions up to, and including, 2.96.6. This is due to missing ownership verification in the REST API routes registered via `Mappress_Api::rest_api_init()`, where the GET `/wp-json/mapp/v1/maps/{mapid}` endpoint uses `'permission_callback' => '__return_true'` and the write endpoints (POST update, DELETE, PATCH mutate, POST clone, POST empty_trash) only check the generic `edit_posts` capability without confirming that the requester owns the targeted map — a gap that is not compensated at the model layer, as `Mappress_Map::get()`, `save()`, `delete()`, `mutate()`, and `empty_trash()` all operate on any caller-supplied map ID without an ownership check. This makes it possible for unauthenticated attackers to read sensitive map data — including POI titles, addresses, coordinates, and body content — for any map on the site by enumerating map IDs, and for authenticated attackers with Contributor-level access and above to modify, delete, trash/restore, or clone any map regardless of its author.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-8839"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L253"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L268"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L328"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L39"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L50"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L75"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_api.php#L90"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L239"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L379"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L493"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.95.10/mappress_map.php#L550"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L253"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L268"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L328"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L39"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L50"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L75"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_api.php#L90"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L239"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L379"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L493"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mappress-google-maps-for-wordpress/tags/2.96.6/mappress_map.php#L550"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/changeset?old_path=/mappress-google-maps-for-wordpress/tags/2.96.6&new_path=/mappress-google-maps-for-wordpress/tags/2.97.1"
  }, {
    "type" : "WEB",
    "url" : "https://www.wordfence.com/threat-intel/vulnerabilities/id/9f402aa7-24d6-448b-a1d3-5ee7c90b39bc?source=cve"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-639" ],
    "severity" : "MODERATE",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-06-06T05:16:29Z"
  }
}

CVSS V3

5.3 MODERATE

Attack Vector Network (AV:N)

Attack Complexity Low (AC:L)

Privileges Required None (PR:N)

User Interaction None (UI:N)

Scope Unchanged (S:U)

Confidentiality None (C:N)

Integrity Low (I:L)

Availability None (A:N)

Vector String

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

Advisory Metadata

Source ID: GHSA-4m8c-59q5-hc8f
Schema Version: 1.4.0
Published: 2026-06-06 06:30
Last Modified: 2026-06-06 06:30
Database Record File: advisories/unreviewed/2026/06/GHSA-4m8c-59q5-hc8f/GHSA-4m8c-59q5-hc8f.json