Cross-site scripting in livecomposer Live Composer – Free WordPress Website Builder
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| livecomposer | Live Composer – Free WordPress Website Builder | up to 2.1.21 | — | No fix listed | CNA |
- Live Composer – Free WordPress Website Builder Vendorlivecomposer Affected up to 2.1.21 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-16778
- 2026-10-03 Alias added: GHSA-hv57-w5f4-r2xr
References
Other 8
- https://www.wordfence.com/threat-intel/vulnerabilities/id/1d072660-515c-4fd9-903b-815447786e03?source=cve
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5508
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5225
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5219
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5502
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L4978
- https://plugins.trac.wordpress.org/browser/live-composer-page-builder/tags/2.1.18/modules/downloads/module.php#L5685
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3705127%40live-composer-page-builder&new=3705127%40live-composer-page-builder
More livecomposer vulnerabilities
- TI-2026-13779 Live Composer <= 2.1.18 - Authenticated (Contributor+) PHP Object Injection via Shortcode CVSS 3.1HIGH 8.8
- TI-2025-12857 Deserialization of untrusted data in livecomposer Live Composer – Free WordPress Website… CVSS 3.1HIGH 7.5
- TI-2026-11211 Live Composer <= 2.1.19 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'custom_id' Shortcode Attribute CVSS 3.1MEDIUM 6.4
- TI-2026-13973 Cross-site scripting in livecomposer Live Composer – Free WordPress Website Builder CVSS 3.1MEDIUM 6.4
- TI-2026-13972 Live Composer <= 2.1.19 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'dslc_custom_field' Shortcode CVSS 3.1MEDIUM 6.4
- TI-2026-13971 Cross-site scripting in livecomposer Live Composer – Free WordPress Website Builder CVSS 3.1MEDIUM 6.4
Sources
- CVE-2026-16778 · CVE Program
- CVE-2026-16778 · NVD
- FIRST EPSS
- GHSA-hv57-w5f4-r2xr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences