CVE-2021-24148Network attack vector

Account takeover via email-only Apple login

Published Mar 18, 2021 · Updated Aug 3, 2024

Authentication bypass in FluxBuilder MStore API before 3.2.0 allows remote attackers to obtain an authentication cookie using an email address. The legacy GET-based Sign in with Apple path accepts the supplied email as account identity and returns a WordPress authentication cookie without requiring an Apple identity token. The endpoint must be exposed and the target account's email address known; the resulting cookie permits impersonation of that WordPress user.

CVSS severity9.8
Critical
EPSS probability3.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in FluxBuilder MStore API before 3.2.0 allows remote attackers to obtain an authentication cookie using an email address. The legacy GET-based Sign in with Apple path accepts the supplied email as account identity and returns a WordPress authentication cookie without requiring an Apple identity token. The endpoint must be exposed and the target account's email address known; the resulting cookie permits impersonation of that WordPress user.

The record

CVE
CVE-2021-24148
Published
Mar 18, 2021
Updated
Aug 3, 2024
Vendor
FluxBuilder
Product
MStore API
Classifications
CWE-287, T1539
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.2.0 <3.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FluxBuilder · MStore APIversion=3.2.0 <3.2.0

Published CVSS scores

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NVDAV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1539Steal Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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