CVE-2026-25010: Share This Image Auth Bypass Flaw

CVE-2026-25010 Overview

CVE-2026-25010 is a Missing Authorization vulnerability [CWE-862] in the ILLID Share This Image plugin for WordPress. The flaw affects all plugin versions up to and including 2.09. Attackers can exploit incorrectly configured access control security levels to interact with plugin functionality that should be restricted. The vulnerability requires no authentication and no user interaction, and it is exploitable over the network. Successful exploitation results in a limited integrity impact, with no direct effect on confidentiality or availability of the host application.

Critical Impact
Unauthenticated attackers can reach plugin actions that lack proper authorization checks, enabling tampering with plugin state on affected WordPress sites.

Affected Products

ILLID Share This Image plugin for WordPress
All versions from n/a through <= 2.09
WordPress sites with the share-this-image plugin installed and active

Discovery Timeline

2026-02-03 - CVE-2026-25010 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2026-25010

Vulnerability Analysis

The Share This Image plugin exposes one or more action handlers that fail to enforce authorization before executing privileged operations. The plugin relies on incorrectly configured access control security levels, meaning the code does not verify the caller has the rights required to invoke the action. This pattern is a textbook Missing Authorization weakness tracked under [CWE-862]. The Patchstack advisory classifies the issue as a broken access control vulnerability affecting versions up to and including 2.09. Because the attack vector is network-based and requires no privileges or user interaction, any visitor capable of issuing HTTP requests to the WordPress site can attempt exploitation. The integrity impact is rated as limited, indicating the attacker can modify a constrained subset of plugin data rather than achieve full site compromise.

Root Cause

The root cause is the absence of capability checks (such as current_user_can()) or nonce validation (such as check_ajax_referer()) on one or more plugin endpoints. WordPress plugins commonly expose admin-ajax.php actions through wp_ajax_ and wp_ajax_nopriv_ hooks. When these hooks are registered without server-side authorization logic, the endpoint becomes reachable by any unauthenticated client. See the Patchstack WordPress Vulnerability Advisory for vendor-specific technical context.

Attack Vector

An attacker sends a crafted HTTP request to the vulnerable plugin endpoint on a target WordPress site. The request invokes a plugin action that should be restricted but is not. The server processes the request without validating the caller's identity or capabilities. The attacker observes a successful response and confirms the action was performed. The vulnerability does not require credentials, social engineering, or proximity to the target.

No verified public proof-of-concept code is available for this vulnerability at the time of writing. Refer to the Patchstack advisory linked above for additional technical details.

Detection Methods for CVE-2026-25010

Indicators of Compromise

Unexpected POST requests to /wp-admin/admin-ajax.php referencing share-this-image action names from unauthenticated sessions.
Anomalous modifications to plugin-managed data or settings without a corresponding administrator login event.
Spikes in traffic to plugin endpoints from a small set of source IP addresses scanning many WordPress hosts.

Detection Strategies

Inspect WordPress access logs for AJAX action calls tied to the share-this-image plugin that originate from clients without an authenticated session cookie.
Correlate plugin-related state changes against the WordPress audit trail to identify actions with no associated user account.
Deploy web application firewall rules that flag requests to plugin endpoints when authorization headers or valid nonces are absent.

Monitoring Recommendations

Enable verbose request logging on admin-ajax.php and any plugin REST routes registered under the plugin namespace.
Monitor for repeated 200 OK responses to unauthenticated POST requests targeting the plugin during reconnaissance windows.
Track the installed plugin inventory across WordPress estates and alert when versions <= 2.09 of share-this-image are detected.

How to Mitigate CVE-2026-25010

Immediate Actions Required

Identify all WordPress instances running the Share This Image plugin and confirm the installed version.
Upgrade the plugin to a fixed release once published by the vendor, or deactivate and remove the plugin if a patched version is not yet available.
Restrict access to wp-admin/admin-ajax.php from untrusted networks where feasible, using upstream WAF or reverse proxy rules.

Patch Information

At the time of NVD publication, the advisory lists affected versions as n/a through <= 2.09. Administrators should consult the Patchstack WordPress Vulnerability Advisory for the latest fixed version information and apply the vendor-supplied update through the WordPress plugin manager.

Workarounds

Deactivate the share-this-image plugin until a patched version is installed.
Apply virtual patching through a web application firewall to block unauthenticated requests to plugin AJAX actions.
Limit administrative endpoints to known IP ranges using .htaccess or reverse proxy access control lists.

bash

# Configuration example: block unauthenticated access to the plugin AJAX action via nginx
location = /wp-admin/admin-ajax.php {
    if ($arg_action ~* "share_this_image") {
        # Require a valid session cookie before forwarding the request
        if ($http_cookie !~* "wordpress_logged_in_") {
            return 403;
        }
    }
    include fastcgi_params;
    fastcgi_pass php_upstream;
}