Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-3453 is a high-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Wordpress (inferred from references). Its CVSS base score is 8.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 31th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-3 (Access Enforcement) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-3453 is an Insecure Direct Object Reference (IDOR) vulnerability, classified under CWE-639, affecting the ProfilePress plugin for WordPress in all versions up to and including 4.16.11. The issue stems from missing ownership validation on the user-controlled change_plan_sub_id parameter within the process_checkout() function. Specifically, the ppress_process_checkout AJAX handler loads a subscription record based on this parameter, intended for plan upgrades, and cancels or expires it without confirming that the subscription belongs to the requesting user.
Authenticated attackers with Subscriber-level access or higher can exploit this vulnerability over the network with low complexity and no user interaction required. By supplying any other user's active subscription ID via the change_plan_sub_id parameter during checkout, attackers can immediately cancel and expire the victim's subscription, resulting in loss of paid access. The vulnerability has a CVSS v3.1 base score of 8.1 (AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H), reflecting high impact on integrity and availability.
Mitigation details are outlined in advisories from Wordfence and code references in the WordPress plugin trac repository. The patch is implemented in changeset 3474509, which modifies the CheckoutController.php file (notably around lines 237, 334, and 342 in version 4.16.9) to add proper ownership checks. Security practitioners should update to ProfilePress version 4.16.12 or later and review access controls on AJAX handlers handling user-specific resources.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-11073
Vulnerability Data
The ProfilePress plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.16.11. This is due to missing ownership validation on the change_plan_sub_id parameter in the process_checkout() function. The ppress_process_checkout AJAX handler accepts…
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a user-controlled subscription ID intended for plan upgrades, loads the subscription record, and cancels/expires it without verifying the subscription belongs to the requesting user. This makes it possible for authenticated attackers, with Subscriber-level access and above, to cancel and expire any other user's active subscription via the change_plan_sub_id parameter during checkout, causing immediate loss of paid access for victims.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Enforcing approved authorizations on every access request structurally stops a user-controlled key from reaching another user's data.
Requiring explicit access-control decisions on each request blocks unauthorized key-driven access.
Least-privilege restrictions limit the scope of data reachable even if a key check is bypassed.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.
Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect missing authorization checks but does not prevent the weakness in production.
Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.
Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.
Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.
Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.
Secure development lifecycle includes authorization design but does not itself implement runtime access checks.