# CVE-2026-70650: GetSimple CMS stored XSS in backup viewer

Source: https://junglewise.ai/threats/cve-2026-70650-getsimple-cms-is-a-content-management-system-cms-and-getsimple  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-01. Updated: 2026-10-05  
License: CC BY 4.0 with a link back

CVE-2026-70650 · Severity: info · Published 2026-10-01

GetSimple CMS is a web-based content management system used to build and maintain websites. An authenticated attacker who can edit pages can inject malicious JavaScript into page fields (content, keywords, description, or menu text) that executes in the browsers of administrators viewing page backups. This allows attackers to perform any action an administrator can perform, including editing themes which could lead to complete server compromise.

Technologies: [GetSimple CMS CE](https://junglewise.ai/threats/technologies/getsimple-cms-ce). Vendors: [GetSimple](https://junglewise.ai/threats/vendors/getsimple).

## Quick answers

**Is CVE-2026-70650 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-70650 being exploited in the wild.

**How severe is CVE-2026-70650?** Informational severity, published 1 October 2026.

**Which products and versions are affected?** GetSimple CMS CE 3.3.22 and prior.

**Is there a fix for CVE-2026-70650?** No fixed version is recorded yet. Escape stored values on output using htmlspecialchars($value, ENT_QUOTES, 'UTF-8') instead of decoding them when printing in admin/backup-edit.php, and remove all htmldecode() and strip_decode() calls used for display of affected fields.</anigation>
<parameter name="timeline">[{"kind":"disclosed","at":"2026-08-05"},{"kind":"advisory","at":"2026-10-01"}] If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-70650 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-70650?** Check whether you run GetSimple CMS CE at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix


Escape stored values on output using htmlspecialchars($value, ENT_QUOTES, 'UTF-8') instead of decoding them when printing in admin/backup-edit.php, and remove all htmldecode() and strip_decode() calls used for display of affected fields.</anigation>
<parameter name="timeline">[{"kind":"disclosed","at":"2026-08-05"},{"kind":"advisory","at":"2026-10-01"}]

## Technical details

An authenticated stored cross-site scripting (XSS) vulnerability exists in admin/backup-edit.php where page fields are HTML-decoded and printed without re-escaping, undoing the encoding applied at save time. The vulnerable attack vector requires an authenticated user with page-editing permissions to inject JavaScript into page metadata or content fields, but viewing the backup requires only a simple GET request with no CSRF protection. A successful exploit allows arbitrary JavaScript execution in an administrator's session context, enabling privilege escalation and potentially remote code execution via theme manipulation.

## Affected products

- GetSimple CMS CE 3.3.22 and prior

## References

- [https://github.com/GetSimpleCMS-CE/GetSimpleCMS-CE/security/advisories/GHSA-p6vf-2xr7-mcf4](https://github.com/GetSimpleCMS-CE/GetSimpleCMS-CE/security/advisories/GHSA-p6vf-2xr7-mcf4)

## Related threats

- [GetSimple CMS CE cross-site request forgery in UpdateCE](https://junglewise.ai/threats/cve-2026-56662-getsimple-cms-is-a-content-management-system-cms-and-getsimple)
- [GetSimple CMS server-side request forgery in update handler](https://junglewise.ai/threats/cve-2026-56661-getsimple-cms-is-a-content-management-system-cms-and-getsimple)
- [GetSimple CMS unrestricted ZIP extraction in UpdateCE plugin](https://junglewise.ai/threats/cve-2026-56660-getsimple-cms-is-a-content-management-system-cms-and-getsimple)
- [GetSimple CMS password reset authentication bypass](https://junglewise.ai/threats/cve-2026-53953-getsimple-cms-is-a-content-management-system-cms-and-getsimple)
- [GetSimple CMS unauthenticated admin account creation via setup script](https://junglewise.ai/threats/cve-2026-53952-getsimple-cms-unauthenticated-admin-account-creation-via-setup)