CVE-2026-23976

Medium

Published: 22 January 2026

Published

22 January 2026

Modified

23 April 2026

KEV Added

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Patch

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CVSS Score v3.1 5.9 CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L

EPSS Score 0.0006 18.8th percentile

Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-23976 is a medium-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 5.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 18.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-15 (Information Output Filtering).

Deeper analysis

CVE-2026-23976 is an Improper Neutralization of Input During Web Page Generation vulnerability (CWE-79), enabling Stored Cross-site Scripting (XSS) in the WP Chill Modula Image Gallery WordPress plugin, known as modula-best-grid-gallery. The issue affects all versions from n/a through 2.13.4, with a CVSS v3.1 base score of 5.9 (AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L).

High-privilege authenticated users, such as administrators (PR:H), can exploit this over the network (AV:N) with low complexity (AC:L) by injecting malicious payloads into gallery inputs. These stored scripts execute in the browser context of other users (UI:R) who view affected pages, with a changed scope (S:C) allowing low-level impacts on confidentiality, integrity, and availability.

Patchstack advisories document the vulnerability and provide further details at https://patchstack.com/database/Wordpress/Plugin/modula-best-grid-gallery/vulnerability/wordpress-modula-image-gallery-plugin-2-13-4-cross-site-scripting-xss-vulnerability?_s_id=cve.

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2026-3825

Vulnerability details

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in WP Chill Modula Image Gallery modula-best-grid-gallery allows Stored XSS.This issue affects Modula Image Gallery: from n/a through <= 2.13.4.

CWE(s): CWE-79

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1059.007 JavaScript Execution

Adversaries may abuse various implementations of JavaScript for execution.

attack.mitre.org →

Why these techniques?

Stored XSS in public-facing WordPress plugin directly enables arbitrary JavaScript execution in victim browsers (T1059.007) after exploitation of the web application (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1