CVE-2026-16778

Description

The Live Composer – Free WordPress Website Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'dslc_module_downloads_output' Shortcode Content in all versions up to, and including, 2.1.21 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The save-time wp_kses_post check is bypassed because the payload is stored as a serialized string containing no HTML tags for kses to tokenize, and the shortcode callback re-emits attacker-controlled values — including view_all_link (href attribute), main_heading_title (h2 body), button_text (anchor body), and button_inline_svg (anchor body) — without any escaping at render time.

Overview

State: PUBLISHED
Assigner (CNA): Wordfence
CVSS severity: MEDIUM
CVSS score: 6.4 / 10
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Effective score: 6.4 / 10 MEDIUM source: CNA overview
CWE(s): CWE-79
Reserved: 2026-07-23
Published: 2026-09-22 07:41 UTC
Last updated: 2026-09-22 10:25 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/16xxx/CVE-2026-16778.json

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-22 08:16:38 UTC
NVD last modified: 2026-09-22 19:04:55 UTC
NVD CVSS v3.1: 6.4 / 10 MEDIUM source: security@wordfence.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Exploitability subscore: 3.1 / 10
Impact subscore: 2.7 / 10
EPSS score: 0.0022 (probability of exploitation in next 30 days)
EPSS percentile: 12.88% vs all CVEs — higher = more likely to be exploited, as of 2026-09-22

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-84298
Assigner: Wordfence
Published: Sep 22, 2026, 7:41:09 AM
Updated: Sep 22, 2026, 10:25:33 AM
EUVD base score (CVSS 3.1): 6.4 / 10
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
EUVD-reported EPSS: 0.2200
Vendors: livecomposer
Products: Live Composer – Free WordPress Website Builder (0 ≤2.1.21)
Aliases: GHSA-hv57-w5f4-r2xr

ENISA description: The Live Composer – Free WordPress Website Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'dslc_module_downloads_output' Shortcode Content in all versions up to, and including, 2.1.21 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The save-time wp_kses_post check is bypassed because the payload is stored as a serialized string containing no HTML tags for kses to tokenize, and the shortcode callback re-emits attacker-controlled values — including view_all_link (href attribute), main_heading_title (h2 body), button_text (anchor body), and button_inline_svg (anchor body) — without any escaping at render time.

EUVD references (8)

Affected products (1)

Vendor	Product	Versions	Platforms
livecomposer	Live Composer – Free WordPress Website Builder	`0` (affected)	—

Vendor references (8)

References embedded in the original CVE record by the assigning CNA.

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (8)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L4978 security@wordfence.com
https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5219 security@wordfence.com
https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5225 security@wordfence.com
https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5502 security@wordfence.com
https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5508 security@wordfence.com
https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5685 security@wordfence.com
https://plugins.trac.wordpress.org/changeset?reponame=&old=3705127%40live-composer-page-builder&new=3705127%40live-composer-page-builder security@wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/1d072660-515c-4fd9-903b-815447786e03?source=cve security@wordfence.com

Remediations (10)

CVE-2026-62778 - Vulnerability Details - OpenCVE

web:app.opencve.io

Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Download and install the Microsoft security update for CVE‑2026‑62778 from the Microsoft Security Response Center. Restart the affected Windows DNS service or reboot the server to confirm the update has taken effect.

2026-09-23 15:46 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-23 15:46 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-23 15:46 UTC
July 18, 2026—Hotpatch KB5121768 (OS Builds 26200.8893 and 26100.8893 ...

web:support.microsoft.com

This out-of-band (OOB) update for Windows 11, version 25H2 and Windows 11, version 24H2 (KB5121768) is cumulative. It includes all improvements from previous security and non-security updates, along with an additional fix . Improvements This OOB update includes the following improvement: [System Performance] This update addresses an issue affecting a limited number of devices with an Intel ...

2026-09-23 15:46 UTC
SAP Security Patch Day - June 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.

2026-09-23 15:46 UTC
August 2026 CVE Advisory Notification - Security

web:support.servicenow.com

Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity

2026-09-23 15:46 UTC
CVE-2026-62878: Patch Windows DNS Server RCE Flaw

web:windowsforum.com

Microsoft published CVE - 2026 -62878 on August 11 as a Windows DNS Server Remote Code Execution Vulnerability, putting systems that run the Windows DNS Server role into the immediate patch -and-verify queue.

2026-09-23 15:46 UTC
August's Patch Tuesday is a monster: 751 fixes, with an exploited ...

web:www.computerworld.com

August's Patch Tuesday is a big one: 751 fixes, an exploited WinSock flaw and plenty of critical Windows, Office and Exchange issues.

2026-09-23 15:46 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-23 15:46 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-23 15:46 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-16778.json.

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