Adfinis Document Merge Service up to 9.0.x XLSX Template Processing special elements in template engine

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Adfinis Document Merge Service up to 9.0.x. Affected by this issue is some unknown functionality of the component XLSX Template Processing. Executing a manipulation can lead to special elements in template engine. This vulnerability appears as CVE-2026-53964. The attack may be performed from remote. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Adfinis Document Merge Service up to 9.0.x and classified as problematic. This vulnerability affects an unknown functionality of the component XLSX Template Processing. The manipulation with an unknown input leads to a special elements in template engine vulnerability. The CWE definition for the vulnerability is CWE-1336. The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-53964 since 06/11/2026. The exploitation appears to be easy. The attack can be initiated remotely. Additional levels of successful authentication are necessary for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1221 by the MITRE ATT&CK project.

Upgrading to version 9.1.0 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.2
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Special elements in template engine
CWE: CWE-1336 / CWE-791 / CWE-790
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Document Merge Service 9.1.0

Timelineinfo

06/11/2026 CVE reserved
10/01/2026 +112 days Advisory disclosed
10/01/2026 +0 days VulDB entry created
10/01/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-53964 (🔒)
GCVE (CVE): GCVE-0-2026-53964
GCVE (VulDB): GCVE-100-412798

Entryinfo

Created: 10/01/2026 22:12
Changes: 10/01/2026 22:12 (64)
Complete: 🔍
Cache ID: 216::103

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