Opennms
CVE-2020-12760
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A08:2025 - Software or Data Integrity Failures
ASVS 5.0
V1 - Encoding and Sanitization Safe deserialization, type allowlists
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 8.8 (HIGH). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could execute arbitrary code through malicious serialized objects by sending crafted requests to the affected application. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAI
An issue was discovered in OpenNMS Horizon before 26.0.1, and Meridian before 2018.1.19 and 2019 before 2019.1.7. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Avoid deserializing untrusted data. Use safe serialization formats (JSON). Implement integrity checks and type allowlists.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in maven
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Deserialization of Untrusted Data (CWE-502), which allows attackers to execute arbitrary code through malicious serialized objects. An issue was discovered in OpenNMS Horizon before 26.0.1, and Meridian before 2018.1.19 and 2019 before 2019.1.7. The ActiveMQ channel configuration allowed for arbitrary deserialization of Java objects (aka ActiveMQ Minion payload deserialization), leading to remote code execution for any authenticated channel user regardless of its assigned permissions. Affected products include: Opennms Opennms Horizon, Opennms Opennms Meridian. Version information: before 26.0.1.
Know when Opennms gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
An issue was discovered in OpenNMS Horizon before 26.0.1, and Meridian before 2018.1.19 and 2019 before 2019.1.7. The ActiveMQ channel configuration allowed for arbitrary deserialization of Java objects (aka ActiveMQ Minion payload deserialization), leading to remote code execution for any authenticated channel user regardless of its assigned permissions.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Insecure deserialization occurs when an application converts serialized data (a stream of bytes representing an object's state) back into a living object without proper validation.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
Affected Products (CPE)NVD
In OpenMNS Horizon 31.0.8 and versions earlier than 32.0.2 and related Meridian versions, any user that has the ROLE_FIL
The Horizon REST API includes a users endpoint in OpenMNS Horizon 31.0.8 and versions earlier than 32.0.2 on multiple pl
OpenNMS has a default password of rtc for the rtc account, which makes it easier for remote attackers to obtain access b
In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation
OpenNMS is accessible via port 9443. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no
In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation
In OpenNMS Horizon, versions opennms-17.0.0-1 through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation-2
In OpenNMS Horizon, versions opennms-18.0.0-1 through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation-2
A BeanShell interpreter in remote server mode runs in OpenMNS Horizon versions earlier than 32.0.2 and in related Meridi
In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation
In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation
OpenNMS Meridian 2016, 2017, 2018 before 2018.1.25, 2019 before 2019.1.16, and 2020 before 2020.1.5, Horizon 1.2 through
NVD
CVE.org
EPSS
GitHub
Exploit-DB