# CVE-2025-66434: An SSTI (Server-Side Template Injection) vulnerability exists in the get_dunning_letter_text method of Frappe ERPNext…

Source: https://junglewise.ai/threats/cve-2025-66434-an-ssti-server-side-template-injection-vulnerability-exists-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-12-15  
License: CC BY 4.0 with a link back

CVE-2025-66434 · Severity: high · CVSS 8.8 · Published 2025-12-15

An SSTI (Server-Side Template Injection) vulnerability exists in the get_dunning_letter_text method of Frappe ERPNext through 15.89.0. The function renders attacker-controlled Jinja2 templates (body_text) using frappe.render_template() with a user-supplied context (doc). Although Frappe uses a custom SandboxedEnvironment, several dangerous globals such as frappe.db.sql are still available in the execution context via get_safe_globals(). An authenticated attacker with access to configure Dunning Type and its child table Dunning Letter Text can inject arbitrary Jinja expressions, resulting in server-side code execution within a restricted but still unsafe context. This can leak database information.

Technologies: [Frappe ERPNext](https://junglewise.ai/threats/technologies/erpnext). Vendors: [Frappe](https://junglewise.ai/threats/vendors/frappe).

## Quick answers

**Is CVE-2025-66434 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-66434 being exploited in the wild.

**How severe is CVE-2025-66434?** High severity, with a CVSS score of 8.8, published 15 December 2025.

**Which products and versions are affected?** Frappe ERPNext. The advisory does not name versions.

**Is there a fix for CVE-2025-66434?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2025-66434?** Check whether you run Frappe ERPNext. 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.

## Affected products

- Frappe ERPNext

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