Chained Quiz: Broken access control

Chained Quiz is affected by broken access control. The vulnerable path is reachable without authentication. A successful request can reach data or an operation that should be restricted to another user or a more privileged role.

CVE / CNA score 5.3 CVSS 3.1 · security@wordfence.com

NVD score Pending NVD has not published its own CVSS assessment.

Component: Chained Quiz
Plugin slug: chained-quiz
Affected: See vendor advisory
Safe version: See mitigation notes
Published: Sep 18, 2025
Weakness: CWE-639 — Authorization Bypass Through User-Controlled Key

This CVE was published Sep 18, 2025 and is one of 23 known issues for this plugin.

What to do

Update, patch or deactivate.

No fixed release is identified. Update Chained Quiz when a confirmed fixed release becomes available; until then, disable and remove it when the site's risk warrants.

No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The Chained Quiz plugin for WordPress is vulnerable to Insecure Direct Object Reference in version 1.3.4 and below via the quiz submission and completion mechanisms due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to hijack and modify other users' quiz attempts by manipulating the chained_completion_id cookie value, allowing them to alter quiz answers, scores, and results of any user. The vulnerability was partially patched in versions 1.3.4 and 1.3.5.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

References

Primary and upstream sources

Data attribution: This product uses the NVD API but is not endorsed or certified by the NVD.

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