CVE-2026-8912

Contest Gallery <= 28.1.6 - Unauthenticated SQL Injection

2026-05-18 00:00
Leonid Semenenko (lsemenenko)

Strategic Overview

Status
Patched in 28.1.7
Affected Plugin
Contest Gallery – Upload & Vote Photos, Media, Sell with PayPal & Stripe
Affected Version
<= 28.1.6
CVSS
7.5High
Weakness type
CWE-89 · Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
CVE
CVE-2026-8912
View all Contest Gallery – Upload & Vote Photos, Media, Sell with PayPal & Stripe vulnerabilities

At a glance

CVE-2026-8912 is a high-severity Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in the Contest Gallery WordPress plugin, affecting versions <= 28.1.6. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high confidentiality impact). Exploitation requires no authentication. The issue is fixed in version 28.1.7; sites on affected versions should update now. Disclosed May 2026, reported by Leonid Semenenko (lsemenenko).

Vulnerability Overview

The Contest Gallery plugin for WordPress is vulnerable to SQL Injection via the 'form_input' parameter in versions up to, and including, 28.1.6. This is due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query inside the unauthenticated 'post_cg_gallery_form_upload' AJAX action (specifically the 'cb' branch of the included users-upload-check.php, where $f_input_id is concatenated unquoted into 'SELECT Field_Content FROM ... WHERE id = $f_input_id'). The endpoint is gated only by a public frontend nonce ('cg1l_action' / 'cg_nonce') that is exposed in the page source of any public gallery page. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality.

CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Contest Gallery <= 28.1.6 carries this weakness at form_input, and reaching it takes no account at all. SQL injection happens when request data is concatenated into a query instead of being bound as a parameter, letting an attacker change the structure of the statement rather than just its values.

A working injection can read any table the database user can see, which on a WordPress install means user records, password hashes and session or API secrets stored in options. For Contest Gallery the fix is 28.1.7: builds <= 28.1.6 are affected, anything from 28.1.7 onward is not.

Remediation

Update to version 28.1.7, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Contest Gallery 28.1.7 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-8912https://www.wordfence.com/threat-intel/vulnerabilities/id/71f2f8c4-00ee-4ab4-b0e0-9ddac46818b3https://nvd.nist.gov/vuln/detail/CVE-2026-8912

Related records

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