Answer in brief
CVE-2026-18742 records a Medium severity (CVSS 6.4) vulnerability in Flatsome <= 3.20.12 - Authenticated (Contributor+) DOM-Based Stored Cross-Site Scripting via 'data-text-sec', 'data-title', and 'title' Attributes via Custom HTML Block. The current sources do not mark it as known exploited. The current feed maps UX-themes/Flatsome (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.4. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps UX-themes/Flatsome (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| UX-themes/Flatsomegeneric | >=0 <=3.20.12 | Not reported |
Published upstream
Nov 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 14, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 14, 2026
The Flatsome theme for WordPress is vulnerable to Stored Cross-Site Scripting via 'data-text-sec', 'data-title', and 'title' Attributes via Custom HTML Block in all versions up to, and including, 3.20.12 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 payload survives server-side sanitization because wp_kses_post permits data-* attributes globally via _wp_add_global_attributes, allowing attacker-controlled values in data-text-sec, data-title, and title attributes to persist in saved post content and be later interpreted as HTML by the ux-countdown, scroll-to, and lightbox-gallery JavaScript behaviors.
Quoted source text, attributed separately from HOL analysis.