Subscriber-level privilege escalation via arbitrary user meta write
Published Apr 9, 2026 · Updated Apr 9, 2026
Authorization bypass in FluxBuilder MStore API 4.18.3 and earlier allows remote authenticated users to modify their own user metadata. The update_user_profile() function decodes the meta_data JSON body and passes each attacker-chosen key and value directly to update_user_meta() without a key allowlist or validation. Subscriber-level access is sufficient to rewrite wp_user_level or plugin authorization flags, enabling privilege escalation or unauthorized account-state changes.
Summary
What happened
Authorization bypass in FluxBuilder MStore API 4.18.3 and earlier allows remote authenticated users to modify their own user metadata. The update_user_profile() function decodes the meta_data JSON body and passes each attacker-chosen key and value directly to update_user_meta() without a key allowlist or validation. Subscriber-level access is sufficient to rewrite wp_user_level or plugin authorization flags, enabling privilege escalation or unauthorized account-state changes.
The record
- CVE
- CVE-2026-3568
- Published
- Apr 9, 2026
- Updated
- Apr 9, 2026
- Vendor
- FluxBuilder
- Product
- MStore API
- Classifications
- CWE-639, T1098
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 9, 2026CVE publishedPublication date reported by the CVE source.
- Apr 9, 2026Record 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.
- Affected versionversion=0 <=4.18.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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