{"id":"CVE-2026-53964","summary":"Document Merge Service vulnerable to RCE via SSTI (xlsx tempaltes)","details":"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.","aliases":["GHSA-w47q-945m-q9pc","PYSEC-2026-3830"],"modified":"2026-10-04T02:30:38.457824741Z","published":"2026-10-01T19:55:07.504Z","database_specific":{"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"},"references":[{"type":"WEB","url":"https://github.com/adfinis/document-merge-service/releases/tag/v9.1.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53964.json"},{"type":"ADVISORY","url":"https://github.com/adfinis/document-merge-service/security/advisories/GHSA-w47q-945m-q9pc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53964"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/adfinis/document-merge-service","events":[{"introduced":"0"},{"fixed":"243368823e7f63865f318519f805b481458a0dcd"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"9.1.0"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v9.0.0","v8.1.0","v8.0.3","v8.0.2","v8.0.1","v8.0.0","v7.3.7","v7.3.6","v7.3.5","v7.3.4","v7.3.3","v7.3.2","v7.3.1","v7.3.0","v7.2.0","v7.1.1","v7.1.0","v7.0.2","v7.0.1","v7.0.0","v6.6.1","v6.6.0","v6.4.5","v6.5.2","v6.5.1","v6.5.0","v6.4.4","v6.4.3","v6.4.2","v6.4.1","v6.4.0","v6.3.1","v6.3.0","v6.2.2","v6.2.1","v6.2.0","v6.1.2","v6.1.1","v6.1.0","v6.0.0","v5.2.1","v5.2.0","v5.1.0","v5.0.6","v5.0.5","v5.0.4","v5.0.3","v5.0.2","v5.0.1","v5.0.0","v4.7.0","v4.6.3","v4.6.2","v4.6.1","v4.6.0","v4.5.0","v4.4.1","v4.4.0","v4.3.0","v4.2.1","v4.2.0","v4.1.0","v4.0.1","v4.0.0-rc.1","v3.0.0","v1.0.0","v0.0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53964.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"}]}