MemberDash: Authorization Bypass Through User-Controlled Key
CVE-2026-18053 is a high-severity authorization bypass through user-controlled key vulnerability in MemberDash from LearnDash, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected MemberDash versions: 1.8.7 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far, and no EPSS exploitation forecast has been published yet.
High severity with no evidence of exploitation so far.
What to do
- Check which version of MemberDash you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| LearnDash | MemberDash | 1.8.7 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (wordfence.com).
Official description
The MemberDash plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.8.7. This is due to a mass-assignment vulnerability in the `user_account_manager()` function's edit_profile branch, where all submitted `$_POST` fields are iterated and directly assigned to the current member object via the `MS_Model` `__set()` magic method with no field allowlist and no capability or ownership check on the submitted `id` parameter. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject an arbitrary user ID via the `id` parameter — overwriting any WordPress user's email address and password, including the site administrator's — and subsequently use those modified credentials to gain full administrative access to the site.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: 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.
How developers prevent this class of flaw
- For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)
Timeline
- CVE record published.
References
Patches and release notes
Other references
Other vulnerabilities in MemberDash
- 9.8 Critical severity
Recent Authorization Bypass Through User-Controlled Key vulnerabilities
- 8.1 High severity
- 8.1 High severity
- 7.1 High severity
- 7.1 High severity
- 8.8 High severity
- 8.8 High severity
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