Contest Gallery <= 28.1.5 — Unauthenticated Privilege Escalation Admin Account Takeover via Registration Confirmation Email-to-ID Type Confusion
CVE-2026-4021Published · Updated Action summary
Affected: ≤28.1.5Update to 28.1.6 or newer
All remediation steps- Severity
- High8.1
- CVSS
- 8.1CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HWhat does this vector mean?
AV:NAttack vector- Network
AC:HAttack complexity- High
PR:NPrivileges required- None
UI:NUser interaction- None
S:UScope- Unchanged
C:HConfidentiality- High
I:HIntegrity- High
A:HAvailability- High
- Weakness
- CWE-287 Improper Authentication
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Contest Gallery Commerce – Upload, Vote & Sell with PayPal & Stripe contest-gallery
- Affected≤ 28.1.5
- Patched in28.1.6
Update to 28.1.6 or newer.
You are affected if you run ≤ 28.1.5. Version 28.1.6 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Contest Gallery Commerce – Upload, Vote & Sell with PayPal & Stripe.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 28.1.6, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Contest Gallery Commerce – Upload, Vote & Sell with PayPal & Stripe to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to Supakiad S. (m3ez).
The Contest Gallery plugin for WordPress is vulnerable to an authentication bypass leading to admin account takeover in all versions up to, and including, 28.1.5. This is due to the email confirmation handler in `users-registry-check-after-email-or-pin-confirmation.php` using the user's email string in a `WHERE ID = %s` clause instead of the numeric user ID, combined with an unauthenticated key-based login endpoint in `ajax-functions-frontend.php`. When the non-default `RegMailOptional=1` setting is enabled, an attacker can register with a crafted email starting with the target user ID (e.g., `[email protected]`), trigger the confirmation flow to overwrite the admin's `user_activation_key` via MySQL integer coercion, and then use the `post_cg1l_login_user_by_key` AJAX action to authenticate as the admin without any credentials. This makes it possible for unauthenticated attackers to take over any WordPress administrator account and gain full site control.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in Contest Gallery Commerce – Upload, Vote & Sell with PayPal & Stripe
All 70| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High8.8 | Authenticated (Author+) Arbitrary File Upload <34.0.3Update to 34.0.3 | CVE-2026-118041 | |
| Medium5.3 | Missing Authorization <34.0.1Update to 34.0.1 | CVE-2026-107447 | |
| Medium6.4 | Authenticated (Subscriber+) Stored Cross-Site Scripting ≤34.0.1Update to 34.0.2 | CVE-2026-111837 | |
| Medium5.3 | Unauthenticated Unauthorized Account Activation ≤33.0.0Update to 33.0.1 | CVE-2026-107120 | |
| High8.8 | Unauthenticated Arbitrary File Upload via 'baseUrlForFacebook' Parameter ≤32.0.1Update to 33.0.0 | CVE-2026-78088 |
- High8.8Authenticated (Author+) Arbitrary File Upload
<34.0.3Update to 34.0.3
- Medium5.3Missing Authorization
<34.0.1Update to 34.0.1
- Medium6.4Authenticated (Subscriber+) Stored Cross-Site Scripting
≤34.0.1Update to 34.0.2
- Medium5.3Unauthenticated Unauthorized Account Activation
≤33.0.0Update to 33.0.1
- High8.8Unauthenticated Arbitrary File Upload via 'baseUrlForFacebook' Parameter
≤32.0.1Update to 33.0.0
Timeline
CVE published
Severity high, CVSS 8.1
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- [object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.