CVE-2026-13447 json
MStore API <= 4.20.0 - Unauthenticated Authentication Bypass via 'id_token' Parameter JWT Forgery
published 2026-09-05 2 mo ago modified 2026-09-08 2 mo ago also EUVD-2026-71838
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- inspireui MStore API – Create Native Android & iOS Apps On The Cloud
Classification
- Weakness
-
- CWE-287 Improper Authentication
- Technology feeds
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#L5
- plugins.trac.wordpress.org /browser/mstore-api/trunk/controllers/flutter-user.php#L940
- plugins.trac.wordpress.org /browser/mstore-api/trunk/controllers/flutter-user.php#L829
- 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/tags/4.18.4/controllers/flutter-user.php#L940
- plugins.trac.wordpress.org /browser/mstore-api/tags/4.18.4/controllers/flutter-user.php#L829
Sources
- CVE List CVE-2026-13447
- NVD CVE-2026-13447
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.