CVE-2025-9121

HighRCEUpdated

Published: 15 December 2025

Published

15 December 2025

Modified

15 April 2026

KEV Added

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Patch

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CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0010 27.9th percentile

Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-9121 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Pentaho Data Integration (inferred from references). Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 27.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Directly mitigates the deserialization vulnerability by requiring timely application of the vendor patch to Pentaho version 10.2.0.4 or later.

SI-10 Information Input Validation good match

prevent

Prevents exploitation of untrusted JSON deserialization by validating inputs and constraining the parser to approved classes and methods.

CM-6 Configuration Settings partial match

prevent

Enforces secure configuration settings for the Pentaho plugin to minimize unsafe deserialization risks through restrictive modes.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

Why these techniques?

Deserialization of untrusted JSON in a public-facing Pentaho Business Analytics Server plugin enables remote code execution, directly mapping to exploitation of public-facing applications.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

Pentaho Data Integration and Analytics Community Dashboard Editor plugin versions before 10.2.0.4, including 9.3.0.x and 8.3.x, deserialize untrusted JSON data without constraining the parser to approved classes and methods.

Deeper analysisAI

CVE-2025-9121 is a deserialization of untrusted data vulnerability (CWE-502) affecting the Pentaho Data Integration and Analytics Community Dashboard Editor plugin in versions before 10.2.0.4, including the 9.3.0.x and 8.3.x series. The issue arises when the plugin deserializes untrusted JSON data without constraining the parser to approved classes and methods, enabling potential gadget chain exploitation. Published on 2025-12-15, it carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its network accessibility and comprehensive impact potential.

An authenticated attacker with low privileges (PR:L) can exploit this vulnerability remotely over the network (AV:N) with low complexity (AC:L) and without requiring user interaction (UI:N). Exploitation could grant high-level impacts on confidentiality, integrity, and availability (C:H/I:H/A:H), likely allowing arbitrary code execution through malicious JSON payloads.

The Hitachi Vantara advisory at https://support.pentaho.com/hc/en-us/articles/41832536185613--Resolved-Hitachi-Vantara-Pentaho-Business-Analytics-Server-Deserialization-of-Untrusted-Data-Versions-before-10-2-0-4-Impacted-CVE-2025-9121 confirms the issue is resolved in version 10.2.0.4, recommending upgrades for all impacted Pentaho Business Analytics Server installations to mitigate the deserialization risk.