CVE-2026-18049 Overview
CVE-2026-18049 affects the WP Photo Album Plus WordPress plugin in versions before 9.2.07.002. The plugin exposes a public endpoint action that skips both capability and nonce checks. The endpoint constructs an option name from a client-supplied value without restricting that value to the plugin's own options. Unauthenticated attackers can read the value of any autoloaded WordPress option whose name ends in the matching suffix. This behavior maps to [CWE-200: Exposure of Sensitive Information to an Unauthorized Actor].
Critical Impact
Unauthenticated remote attackers can extract sensitive autoloaded WordPress option values, potentially including third-party plugin secrets and site configuration data.
Affected Products
- WP Photo Album Plus WordPress plugin versions prior to 9.2.07.002
- WordPress installations with the vulnerable plugin activated
- Public-facing WordPress sites exposing the plugin's AJAX endpoint
Discovery Timeline
- 2026-08-12 - CVE-2026-18049 published to NVD
- 2026-08-12 - Last updated in NVD database
Technical Details for CVE-2026-18049
Vulnerability Analysis
The vulnerability resides in one of the plugin's public endpoint actions. The handler processes requests without verifying user capabilities or WordPress nonces. This design allows any unauthenticated visitor to trigger the action.
The handler then builds a WordPress option name by concatenating a client-supplied string with a fixed component. It does not enforce that the resulting name belongs to the plugin's own option namespace. The handler subsequently retrieves the option value using WordPress core functions and returns it to the caller.
Because the retrieval is restricted to autoloaded options, attackers can enumerate any option whose name ends in the matching suffix. Autoloaded options frequently contain API keys, integration tokens, and internal configuration values written by other plugins.
Root Cause
The root cause is the combination of missing authorization checks and unrestricted input used to construct a sensitive identifier. The endpoint trusts unauthenticated input for a value that should be constrained to a fixed allow-list of plugin-owned option names. WordPress plugin development guidelines require capability checks with current_user_can() and nonce validation with check_ajax_referer() on state-changing or sensitive AJAX handlers.
Attack Vector
Exploitation occurs over the network against the WordPress admin-ajax.php endpoint. The attacker sends an HTTP request that invokes the vulnerable plugin action with a crafted parameter. The parameter is chosen so that the resulting option name matches a target autoloaded option ending in the expected suffix. The server responds with the option value. No authentication, user interaction, or elevated privileges are required. See the WPScan Vulnerability Report for additional technical detail.
Detection Methods for CVE-2026-18049
Indicators of Compromise
- Unauthenticated requests to /wp-admin/admin-ajax.php referencing WP Photo Album Plus action names
- Repeated requests iterating over option-name suffix values from a single source IP
- Anomalous response sizes from the plugin's AJAX endpoint containing serialized option data
Detection Strategies
- Review web server access logs for high-volume POST or GET requests to admin-ajax.php with the vulnerable plugin's action parameter
- Correlate unauthenticated AJAX requests with response bodies that contain configuration-like key-value pairs
- Alert on requests where the client-supplied option-name fragment does not match values generated by legitimate plugin usage
Monitoring Recommendations
- Enable WordPress request auditing via a security plugin or WAF to capture plugin action parameters
- Baseline normal traffic to admin-ajax.php and flag deviations in request rate or parameter patterns
- Monitor outbound alerts from third-party services whose API keys are stored in autoloaded options for unexpected use
How to Mitigate CVE-2026-18049
Immediate Actions Required
- Update WP Photo Album Plus to version 9.2.07.002 or later on all WordPress sites
- Rotate secrets and API keys stored in WordPress autoloaded options after confirming patch installation
- Audit installed plugins and remove WP Photo Album Plus if the site does not require its functionality
Patch Information
The vendor addressed the issue in WP Photo Album Plus version 9.2.07.002. The fix adds capability and nonce checks on the affected public endpoint and restricts the constructed option name to the plugin's own namespace. Refer to the WPScan Vulnerability Report for advisory details.
Workarounds
- Deactivate the WP Photo Album Plus plugin until the patched version can be deployed
- Block unauthenticated requests to admin-ajax.php that reference the vulnerable plugin action using a web application firewall rule
- Restrict access to /wp-admin/admin-ajax.php from untrusted networks where feasible
# Example WAF rule blocking unauthenticated calls to the vulnerable action
# Replace <plugin_action_name> with the specific action identified in the advisory
SecRule REQUEST_URI "@contains /wp-admin/admin-ajax.php" \
"chain,phase:2,deny,status:403,id:1026180490"
SecRule ARGS:action "@streq <plugin_action_name>"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
