CVE-2026-13447
MStore API <= 4.20.0 - Unauthenticated Authentication Bypass via 'id_token' Parameter JWT Forgery
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
9.8
MStore API <= 4.20.0 - Unauthenticated Authentication Bypass via 'id_token' Parameter JWT Forgery
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.
- Record
CVE-2026-13447- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2026-71838
9.8
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.
- Record
EUVD-2026-71838- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6wfp-pwm3-667v
9.8
The Mstore Api plugin for WordPress is vulnerable to Authentication Bypass via JWT Forgery in...
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.
- Record
GHSA-6wfp-pwm3-667v- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287
- Updated
- 2026-11-02
NVD
9.8
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.
- Record
CVE-2026-13447- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | abraxas/CVE-2026-13447 | 2026-09-19 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-13447 is a critical vulnerability (CVSS 9.8) in Inspireui Mstore Api – Create Native Android & Ios Apps On The Cloud, published September 5, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.69%, the 53rd percentile. No source names a fixed version.
References
wordfence.com/threat-intel/vulnerabilities/id/4a1127af-74f6-4748-9aee-5a8c6c2766a4?source=cve
plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/helpers/firebase-phone-auth-helper.php
plugins.trac.wordpress.org/browser/mstore-api/trunk/controllers/flutter-user.php
plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/helpers/firebase-phone-auth-helper.php
plugins.trac.wordpress.org/browser/mstore-api/tags/4.18.4/controllers/flutter-user.php
nvd.nist.gov/vuln/detail/CVE-2026-13447
github.com/advisories/GHSA-6wfp-pwm3-667v