# CVE-2026-107903: Joomla Extension - balbooa.com - Stored XSS in reviews via inconsistent sanitization in Gridbox < 2.20.5.0

Status: published. Published: 2026-11-05. Updated: 2026-11-05.

Joomla Extension - balbooa.com - Stored XSS in reviews via inconsistent sanitization in Gridbox < 2.20.5.0

## Remediation

No remediation reported in collected sources

## Affected products and versions

- balbooa.com / Gridbox extension for Joomla (com_gridbox): 1.0.0-2.20.4.2 (affected). Source: CNA: Joomla

## Severity and prioritization

- CVSS 4.0: 8.6 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N; source: CNA: Joomla

- CVSS 3.1: 8.3 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L; source: ADP: CISA-ADP

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-79

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.balbooa.com/gridbox (CNA: Joomla; product)

## Provenance

- CNA: Joomla: https://www.cve.org/CVERecord?id=CVE-2026-107903; retrieved 2026-11-05; source updated 2026-11-05

Revision: e4ba27066d4e359d1519940ba42f69e19caf7d8ffbfee25067a9c63a78e89070

Canonical: https://y2.dev/cve/CVE-2026-107903

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