Form Block: cross-site scripting
No attacker login is required. Attacker-controlled content is rendered in browser output without sufficient neutralization, allowing script execution under the site's origin when a victim encounters the affected output. The endpoint, field, rendering function and victim role are undisclosed. The export does not distinguish stored from reflected XSS. The supplied vector reports limited confidentiality impact, limited integrity impact, limited availability impact. Victim interaction is required by the vector. Affected versions: <= 1.8.1. The authoritative export identifies 1.8.2 as fixed for this CVE.
- Component
- Form Block
- Plugin slug
form-block- Affected
- n/a through 1.8.1
- Safe version
1.8.2- Published
- Oct 06, 2026
This CVE was published Oct 06, 2026 and is one of 3 known issues for this plugin.
Update, patch or deactivate.
Update Form Block to 1.8.2 or a later supported release. Application-level remediation: Validate accepted input and apply context-appropriate escaping at every output sink. Restrict who may submit content and remove any persisted malicious values.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
Unauthenticated Cross Site Scripting (XSS) in Form Block <= 1.8.1 versions.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L