CVE-2026-96840

Status: DeferredHigh (7.2)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Base score: 7.2

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.24%
Percentile among all scored CVEs: 14
Score date: 10/13/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access60 %
Primary impactT1059.007 JavaScriptexecution55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

🛡️ ATT&CK mitigations that cover these techniques

Vulnerability Scanning Restrict Web-Based Content Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Postx — Post Grid Gutenberg Blocks^AI

CWEs

CWE-79

References

Raw JSON (NVD)

Show

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          "integrityImpact": "LOW",
          "userInteraction": "NONE",
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  "published": "2026-10-10T07:16:42.767",
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      "url": "https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.41/addons/builder/blocks/Archive_Title.php#L144",
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      "url": "https://plugins.trac.wordpress.org/browser/ultimate-post/tags/5.0.41/addons/builder/blocks/Archive_Title.php#L98",
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    {
      "lang": "en",
      "value": "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."
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  "lastModified": "2026-10-13T13:30:21.620",
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