CVE-2026-87839 Overview
CVE-2026-87839 affects the Tripzzy WordPress plugin in versions prior to 1.5.1. The plugin exposes an AJAX action to unauthenticated users without authorization checks or object identifier validation. Attackers can invoke this action to permanently delete arbitrary comments on affected WordPress sites.
The flaw is classified under [CWE-284] Improper Access Control. It impacts data integrity by allowing destruction of user-generated content without any authentication. The vulnerability requires no user interaction and is exploitable remotely over the network.
Critical Impact
Unauthenticated remote attackers can permanently delete any comment on a WordPress site running a vulnerable Tripzzy plugin version, causing irreversible loss of user-generated content.
Affected Products
- Tripzzy WordPress plugin versions prior to 1.5.1
- WordPress sites with the Tripzzy plugin installed and activated
- All hosting environments running the vulnerable plugin version
Discovery Timeline
- 2026-09-20 - CVE-2026-87839 published to NVD
- 2026-09-21 - Last updated in NVD database
Technical Details for CVE-2026-87839
Vulnerability Analysis
The Tripzzy plugin registers an AJAX endpoint accessible to unauthenticated visitors through the WordPress wp_ajax_nopriv_ hook family. The handler performs a comment deletion operation but omits two required security controls.
First, the endpoint lacks a capability check such as current_user_can('moderate_comments'). Second, the handler does not verify that the supplied comment identifier belongs to an object the caller is entitled to modify. The combination allows any anonymous request to delete any comment ID.
The vulnerability affects data integrity rather than confidentiality or availability of the underlying system. Comment deletion is permanent and cannot be reversed without database backups.
Root Cause
The root cause is missing access control [CWE-284] on an AJAX action exposed to unauthenticated users. The handler trusts client-supplied input for the target object identifier and neither validates ownership nor enforces a nonce or capability requirement before executing wp_delete_comment() or an equivalent database operation.
Attack Vector
An attacker sends a crafted HTTP POST request to /wp-admin/admin-ajax.php referencing the vulnerable Tripzzy AJAX action and an arbitrary comment ID. No authentication, no session, and no user interaction are required. The attacker can enumerate comment IDs sequentially to delete all comments on the site.
The vulnerability is exploitable over the network from any source that can reach the WordPress installation. Refer to the WPScan Vulnerability Advisory for technical details on the vulnerable action name and parameters.
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Stop Identity AttacksDetection Methods for CVE-2026-87839
Indicators of Compromise
- Unexpected disappearance of comments across posts and pages, particularly in bulk or sequential ID order.
- HTTP POST requests to /wp-admin/admin-ajax.php from unauthenticated sources referencing Tripzzy plugin actions.
- Web server access logs showing repeated admin-ajax.php calls with incrementing comment_id or similar identifier parameters.
Detection Strategies
- Monitor wp_comments table row counts and alert on unexpected deletions or large drops in comment volume.
- Enable WordPress audit logging plugins to record comment deletion events with source IP and authentication context.
- Correlate web access logs for admin-ajax.php POST requests lacking valid session cookies with subsequent comment removal.
Monitoring Recommendations
- Deploy a Web Application Firewall (WAF) rule to log and rate-limit unauthenticated admin-ajax.php requests targeting Tripzzy actions.
- Schedule regular database integrity snapshots so comment loss can be identified and restored quickly.
- Track plugin version inventory across managed WordPress instances and flag any Tripzzy install below 1.5.1.
How to Mitigate CVE-2026-87839
Immediate Actions Required
- Update the Tripzzy plugin to version 1.5.1 or later on all WordPress installations.
- Audit wp_comments and restore deleted comments from backup if unexpected loss is observed.
- Review web server logs since the plugin was installed for suspicious admin-ajax.php activity.
Patch Information
The vendor addressed CVE-2026-87839 in Tripzzy version 1.5.1. The fix introduces authorization checks and validates the identifier of the object being removed before executing deletion. Details are available in the WPScan Vulnerability Advisory.
Workarounds
- Deactivate the Tripzzy plugin until the update to 1.5.1 can be applied.
- Add WAF rules to block unauthenticated POST requests to admin-ajax.php that reference the vulnerable Tripzzy action name.
- Restrict access to /wp-admin/admin-ajax.php at the reverse proxy layer for requests originating outside expected geographies where feasible.
# Example WAF rule pattern (ModSecurity syntax)
SecRule REQUEST_URI "@endsWith /wp-admin/admin-ajax.php" \
"chain,phase:2,deny,status:403,id:1008783,msg:'Block Tripzzy unauth comment delete'"
SecRule ARGS:action "@rx (?i)tripzzy.*(delete|remove).*comment" \
"chain"
SecRule &REQUEST_COOKIES:/wordpress_logged_in_/ "@eq 0"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
