Document Merge Service is a document template merge service providing an API to manage templates and merge them with given data. Prior to version 9.1.0, 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. This issue has been patched in version 9.1.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-1336"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53964.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "9.1.0"
}
],
"source": [
"AFFECTED_FIELD",
"REFERENCES"
]
}