MStore API < 4.21.0 - Unauthenticated Account Takeover via Firebase Phone Authentication (CVE-2026-16030) | HOL Guard CVE

High · CVSS 8.1CVE-2026-16030

MStore API < 4.21.0 - Unauthenticated Account Takeover via Firebase Phone Authentication

Answer in brief

CVE-2026-16030 records a High severity (CVSS 8.1) vulnerability in MStore API < 4.21.0 - Unauthenticated Account Takeover via Firebase Phone Authentication. The current sources do not mark it as known exploited. The current feed maps Unknown/MStore API (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 7, 2026Updated Aug 26, 2026Source checked Sep 21, 2026First seen by HOL Aug 7, 2026Material review Aug 26, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Unknown/MStore API (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Unknown/MStore APIgeneric	>=0 <4.21.0	4.21.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for Unknown/MStore API.
Review the reported fix. Update Unknown/MStore API to 4.21.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 7, 2026

Sources and claim methodology

Source referencewpscan.com

Upstream source description

The MStore API WordPress plugin before 4.21.0 does not correctly verify the cryptographic signature of the token used to authenticate its phone-based login, allowing unauthenticated attackers who know a registered user's phone number to forge a token and take over that user's account, including administrator accounts.

Quoted source text, attributed separately from HOL analysis.