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MStore API <= 4.20.0 — Unauthenticated Authentication Bypass via 'id_token' Parameter JWT Forgery

CVE-2026-13447Published · Updated

Action summary

Affected: ≤4.20.0Update to 4.21.1 or newer

All remediation steps
Watch plugin
Severity
Critical9.8
CVSS
9.8
CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
What does this vector mean?
AV:N Attack vector
Network
AC:L Attack complexity
Low
PR:N Privileges required
None
UI:N User interaction
None
S:U Scope
Unchanged
C:H Confidentiality
High
I:H Integrity
High
A:H Availability
High
Weakness
CWE-287 Improper Authentication
Required access
No account needed
Exploit prediction (EPSS)
No score
CISA KEV
Not listed
On this page8

Am I affected?

MStore API – Create Native Android & iOS Apps On The Cloud mstore-api

  1. Affected≤ 4.20.0
  2. Patched in4.21.1

Update to 4.21.1 or newer.

You are affected if you run ≤ 4.20.0. Version 4.21.1 and later are not affected by this issue.

  • Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under MStore API – Create Native Android & iOS Apps On The Cloud.
  • No admin access? Run a passive check of your site. It reads public files only.
  • No account is needed to exploit this. Treat any exposed site on an affected version as at risk.

What to do

  1. Update to version 4.21.1, or a newer patched version
  2. Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
  3. Watch MStore API – Create Native Android & iOS Apps On The Cloud to get an email when the next vulnerability is published.

Advisory

Source description from Wordfence Intelligence, credited to t4g0.

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.

Exploits & references

Proof-of-concept & detection

No public proof-of-concept or detection template is known for this vulnerability.

Advisories & patches

More in MStore API – Create Native Android & iOS Apps On The Cloud

All 39
More vulnerabilities in MStore API – Create Native Android & iOS Apps On The Cloud
SeverityVulnerabilityCVEPublished
Medium4.34.22.0 - Authenticated (Subscriber+) Payment Bypass
4.21.1 – 4.22.0Update to 4.22.1
CVE-2026-97219
Medium4.3Missing Authorization to Authenticated (Subscriber+) Arbitrary Order Completion
<4.21.1Update to 4.21.1
CVE-2026-18233
Medium6.3Missing Authorization
<4.21.1Update to 4.21.1
CVE-2026-18234
Critical9.8Unauthenticated Privilege Escalation
≤4.20.0Update to 4.21.0
CVE-2026-27543
Medium5.3Missing Authorization
≤4.20.0Update to 4.21.0
CVE-2026-16038

Timeline

  1. CVE published

    Severity critical, CVSS 9.8

  2. Record last updated

Sources & licenses

Wordfence record
Vulnerability data
Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
CVE® identifiers
[object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
CVSS / CWE
National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
VulnCrest content
Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.

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