A AegiFlow
HIGHCVSS 7.2

CVE-2026-53964

CVE-2026-53964 updated by NVD

Published
2026-08-19
Modified
2026-10-04
Sources
github-advisory, nvd

Summary

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.

Affected packages

EcosystemPackageAffected versionsFixed versions
PyPIdocument-merge-service—9.1.0

Remediation: Upgrade to 9.1.0 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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