CVE-2026-13447: Software Security Vulnerability Vulnerability

CRITICAL
Advisory Identifier: GHSA-6wfp-pwm3-667v
Share
CVSS 9.8
CWE-287
Published
Advisory Summary

CVE-2026-13447 is a CRITICAL (CVSS 9.8) security vulnerability vulnerability (CWE-287: Improper Authentication) affecting Software libraries in the Maven ecosystem. The weakness occurs when when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.. Remediation is available in the latest vendor maintenance releases.

CVE-2026-13447 at a Glance

CVE Identifier CVE-2026-13447
GHSA Identifier GHSA-6wfp-pwm3-667v
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-287: Improper Authentication
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.8

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:H/I:H/A:H).

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 High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-13447

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-2026-13447, 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-287: Improper Authentication, where when an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. 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 Mstore Api plugin for WordPress is vulnerable to Authentication Bypass via JWT Forgery in versions up to, and including, 4.20.0 This is due to missing cryptographic signature verification in the FirebasePhoneAuthHelper::verify_id_token() function, which decodes and validates Firebase ID token claims (alg, kid, aud, iss) but never calls openssl_verify() or any equivalent to validate the JWT signature against Google's actual public key certificates. This makes it possible for unauthenticated attackers to forge a Firebase Phone Auth JWT signed with a self-generated RSA key pair and impersonate any phone number, resulting in unauthorized access to existing WordPress accounts or creation of new arbitrary accounts.

References

NVD — CVE-2026-13447 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-13447
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/flutter-user.php#L829
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/flutter-user.php#L940
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/helpers/firebase-phone-auth-helper.php#L5
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/flutter-user.php#L829
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/flutter-user.php#L940
plugins.trac.wordpress.org/browser/mstore-api/... WEB
https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/helpers/firebase-phone-auth-helper.php#L5
www.wordfence.com/threat-intel/vulner... WEB
https://www.wordfence.com/threat-intel/vulnerabilities/id/4a1127af-74f6-4748-9aee-5a8c6c2766a4?source=cve

Frequently Asked Questions

What is CVE-2026-13447?
CVE-2026-13447 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-287: Improper Authentication.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2026-13447?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2026-13447?
CVE-2026-13447 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-13447?
CVE-2026-13447 is classified under CWE-287: Improper Authentication (When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.).
How can I check Maven dependencies for CVE-2026-13447?
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-6wfp-pwm3-667v",
  "modified" : "2026-09-05T06:32:38Z",
  "published" : "2026-09-05T06:32:37Z",
  "aliases" : [ "CVE-2026-13447" ],
  "details" : "The Mstore Api plugin for WordPress is vulnerable to Authentication Bypass via JWT Forgery in versions up to, and including, 4.20.0 This is due to missing cryptographic signature verification in the FirebasePhoneAuthHelper::verify_id_token() function, which decodes and validates Firebase ID token claims (alg, kid, aud, iss) but never calls openssl_verify() or any equivalent to validate the JWT signature against Google's actual public key certificates. This makes it possible for unauthenticated attackers to forge a Firebase Phone Auth JWT signed with a self-generated RSA key pair and impersonate any phone number, resulting in unauthorized access to existing WordPress accounts or creation of new arbitrary accounts.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-13447"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/flutter-user.php#L829"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/flutter-user.php#L940"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/helpers/firebase-phone-auth-helper.php#L5"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/flutter-user.php#L829"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/flutter-user.php#L940"
  }, {
    "type" : "WEB",
    "url" : "https://plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/helpers/firebase-phone-auth-helper.php#L5"
  }, {
    "type" : "WEB",
    "url" : "https://www.wordfence.com/threat-intel/vulnerabilities/id/4a1127af-74f6-4748-9aee-5a8c6c2766a4?source=cve"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-287" ],
    "severity" : "CRITICAL",
    "github_reviewed" : false,
    "github_reviewed_at" : null,
    "nvd_published_at" : "2026-09-05T06:17:09Z"
  }
}