PT-2026-80321 · Pypi · Document Merge Service

Published

2026-08-19

·

Updated

2026-08-19

CVSS v3.1

7.2

High

VectorAV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Impact

A remote code execution (RCE) via server-side template injection (SSTI) allows for user supplied code to be executed in the server's context where it is executed as the document-merge-server user with the UID 901 thus giving an attacker considerable control over the container. The vulnerability is limited to XLSX templates, were the xltpl library uses a npn-sandboxed Jinja environment for the processing of the template.

Patches

It has been patched in v9.1.0

Workarounds

Disable the upload/usage of XLSX templates.

References

Are there any links users can visit to find out more?
https://book.hacktricks.xyz/pentesting-web/ssti-server-side-template-injection/jinja2-ssti

Fix

Found an issue in the description? Have something to add? Feel free to write us 👾
dbugs@ptsecurity.com

Weakness Enumeration

CWE-1336

Related Identifiers

GHSA-W47Q-945M-Q9PC

Affected Products

Document Merge Service