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Fencer Intel
critical 9.8

CVE-2025-66438 json

A Server-Side Template Injection (SSTI) vulnerability exists in the Frappe ERPNext through 15.89.0 Print Format rendering mechanism.

published 10mo ago modified 26d ago also EUVD-2025-203388

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits
0
none known

Summary

A Server-Side Template Injection (SSTI) vulnerability exists in the Frappe ERPNext through 15.89.0 Print Format rendering mechanism. Specifically, the API frappe.www.printview.get_html_and_style() triggers the rendering of the html field inside a Print Format document using frappe.render_template(template, doc) via the get_rendered_template() call chain. Although ERPNext wraps Jinja2 in a SandboxedEnvironment, it exposes sensitive functions such as frappe.db.sql through get_safe_globals(). An authenticated attacker with permission to create or modify a Print Format can inject arbitrary Jinja expressions into the html field. Once the malicious Print Format is saved, the attacker can call get_html_and_style() with a target document (e.g., Supplier or Sales Invoice) to trigger the render process. This leads to information disclosure from the database, such as database version, schema details, or sensitive values, depending on the injected payload. Exploitation flow: Create a Print Format with SSTI payload in the html field; call the get_html_and_style() API; triggers frappe.render_template(template, doc) inside get_rendered_template(); leaks database information via frappe.db.sql or other exposed globals.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
total
Assessed
10mo ago

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • notion.so https://www.notion.so/SSTI-bug-5-239e6086eadc80a48f17c1257a604d2c?source=copy_link referenced PoC, tagged "exploit" by a source, unverified
  • iamanc.github.io https://iamanc.github.io/post/erpnext-ssti-bug-5 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Classification

Weakness
  • CWE-1336 Improper Neutralization of Special Elements Used in a Template Engine
  • CWE-94 Improper Control of Generation of Code

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.