wpxpo Post Grid Gutenberg Blocks Plugin up to 5.1.0 on WordPress Output Escaping Archive_Title.php display_name cross site scripting

Summaryinfo

A vulnerability has been found in wpxpo Post Grid Gutenberg Blocks Plugin up to 5.1.0 and classified as problematic. Affected by this issue is some unknown functionality of the file Archive_Title.php of the component Output Escaping. The manipulation of the argument display_name leads to cross site scripting. This vulnerability is listed as CVE-2026-96840. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in wpxpo Post Grid Gutenberg Blocks Plugin up to 5.1.0. This issue affects an unknown part of the file Archive_Title.php of the component Output Escaping. The manipulation of the argument display_name with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

The Post Grid Gutenberg Blocks – PostX plugin for WordPress is vulnerable to Stored Cross-Site Scripting via display_name User Field in all versions up to, and including, 5.1.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. WordPress core's pre_user_display_name filter encodes &, <, and > but leaves double-quotes intact (ENT_NOQUOTES), allowing a Subscriber-level user to store a double-quote in their display_name via /wp-admin/profile.php that subsequently breaks out of the alt="" attribute at Archive_Title.php:144.

The advisory is shared at wordfence.com. The identification of this vulnerability is CVE-2026-96840 since 09/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

By approaching the search of inurl:Archive_Title.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• WordPress Plugin

Vendor

• wpxpo

Name

• Post Grid Gutenberg Blocks Plugin

Version

• 5.0
• 5.1.0

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion