CVE-2025-66434
RCE in Frappe Erpnext ≤ 15.89.0
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2025-66434 is a high-severity Code Injection (CWE-94) vulnerability in Frappe Erpnext. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Template Injection (T1221); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-66434 is a Server-Side Template Injection (SSTI) vulnerability in the get_dunning_letter_text method of Frappe ERPNext through version 15.89.0. The method renders attacker-controlled Jinja2 templates from the body_text field using frappe.render_template() with a user-supplied context (doc). Although Frappe employs a custom SandboxedEnvironment, dangerous globals such as frappe.db.sql remain accessible via get_safe_globals(), enabling execution of arbitrary Jinja expressions. The issue is associated with CWE-94 (Improper Control of Generation of Code) and CWE-1336 (Incorrect Handling of Shared Resource Lifetime), and carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
An authenticated attacker with permissions to configure Dunning Type and its child table Dunning Letter Text can exploit this vulnerability over the network with low complexity and no user interaction required. By injecting malicious Jinja expressions into the body_text, the attacker achieves server-side code execution within the restricted but unsafe sandbox context, potentially leaking sensitive database information through functions like frappe.db.sql.
Details on the vulnerability, including potential mitigation strategies, are documented in advisories at https://iamanc.github.io/post/erpnext-ssti-bug-1 and https://www.notion.so/SSTI-bug-1-239e6086eadc8096bfcfe90551a3a483?source=copy_link.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-203397
Vulnerability Data
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…
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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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.3.2V1.3.7V1.3.10V1.3.1
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation finds code paths that accept and execute externally influenced strings.
Input validation directly stops untrusted data from being used to construct executable code without neutralization.
Least privilege limits the damage an injected code fragment can perform once executed.
Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.
Security engineering principles require use of safe templating APIs and proper escaping of external input.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-06's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).
PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect template-injection flaws but does not itself implement neutralization controls.
Secure development life cycle mandates input validation and sanitization that directly prevents template-injection weaknesses.
Application security requirements explicitly call for neutralizing special elements in template engines.
Secure architecture principles reduce the likelihood of unsafe template processing but do not prescribe specific neutralization techniques.
Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.
Controls that restrict unauthorized or malicious code from being introduced via external networks or removable media limit opportunities for an attacker to inject and execute arbitrary code.