Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.36% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-3568High confidence
MStore API <= 4.18.3 - Authenticated (Subscriber+) Insecure Direct Object Reference to Arbitrary User Meta Update
inspireui · MStore API – Create Native Android & iOS Apps On The Cloud
4.3MediumCVSS 3.1
Scheduled
Fix not verifiedMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Medium, unchanged from published severity.unchanged
Compensating controls
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs inspireui MStore API – Create Native Android & iOS Apps On The Cloud and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Fix not verified01
What, why and how
The MStore API plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.18.3. This is due to the update_user_profile() function in controllers/flutter-user.php processing the 'meta_data' JSON parameter without any allowlist, blocklist, or validation of meta keys. The function reads raw JSON from php://input (line 1012), decodes it (line 1013), authenticates the user via cookie validation (line 1015), and then directly iterates over the user-supplied meta_data array passing arbitrary keys and values to update_user_meta() (line 1080) with no sanitization or restrictions. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify arbitrary user meta fields on their own accounts, including sensitive fields like wp_user_level (to escalate to administrator-level legacy checks), plugin-specific authorization flags (e.g., _wpuf_user_active, aiowps_account_status), and billing/profile fields with unsanitized values (potentially enabling Stored XSS in admin contexts). Note that wp_capabilities cannot be directly exploited this way because it requires a serialized array value, but wp_user_level (a simple integer) and numerous plugin-specific meta keys are exploitable.
What
The MStore API plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.18.3. This is due to the update_user_profile() function in controllers/flutter-user.php processing the 'meta_data' JSON parameter without any allowlist, blocklist, or validation of meta keys. The function reads raw JSON from php://input (line 1012), decodes it (line 1013), authenticates the user via cookie validation (line 1015), and then directly iterates over the user-supplied meta_data array passing arbitrary keys and values to update_user_meta() (line 1080) with no sanitization or restrictions. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify arbitrary user meta fields on their own accounts, including sensitive fields like wp_user_level (to escalate to administrator-level legacy checks), plugin-specific authorization flags (e.g., _wpuf_user_active, aiowps_account_status), and billing/profile fields with unsanitized values (potentially enabling Stored XSS in admin contexts). Note that wp_capabilities cannot be directly exploited this way because it requires a serialized array value, but wp_user_level (a simple integer) and numerous plugin-specific meta keys are exploitable.
Why
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
The MStore API plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.18.3. This is due to the update_user_profile() function in controllers/flutter-user.php processing the 'meta_data' JSON parameter without any allowlist, blocklist, or validation of meta keys. The function reads raw JSON from php://input (line 1012), decodes it (line 1013), authenticates the user via cookie validation (line 1015), and then directly iterates over the user-supplied meta_data array passing arbitrary keys and values to update_user_meta() (line 1080) with no sanitization or restrictions. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify arbitrary user meta fields on their own accounts, including sensitive fields like wp_user_level (to escalate to administrator-level legacy checks), plugin-specific authorization flags (e.g., _wpuf_user_active, aiowps_account_status), and billing/profile fields with unsanitized values (potentially enabling Stored XSS in admin contexts). Note that wp_capabilities cannot be directly exploited this way because it requires a serialized array value, but wp_user_level (a simple integer) and numerous plugin-specific meta keys are exploitable.
Why
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Authorization Bypass Through User-Controlled Key → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-639 ↗
CWE-639: Authorization Bypass Through User-Controlled Key. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited loss.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix not verified
- Affected
- MStore API – Create Native Android & iOS Apps On The Cloud: ≤ 4.18.3
- Fixed
- No fixed version is explicitly recorded in the structured CVE data.
- Action
- No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 9 Apr 2026 · Last source change 9 Apr 2026, 12:59 UTC · CWE-639 · Authorization Bypass Through User-Controlled Key
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-20840
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.