CVE-2026-53964
Published:August 19, 2026
Updated:August 20, 2026
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" (https://github.com/adfinis/document-merge-service/releases/tag/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
Related Resources (3)
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Contact UsCVSS v4
Base Score:
8.6
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.2
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Improper Neutralization of Special Elements Used in a Template Engine