CVE-2020-12760Network attack vector

Authenticated code execution via trusted object messages

Published May 11, 2020 · Updated Aug 4, 2024

Java deserialization in OpenNMS Horizon and Meridian allows remote authenticated users to execute code through the ActiveMQ channel. The daemon's ActiveMQ connection factory sets trustAllPackages to true, causing object messages from channel users to be deserialized without a package allowlist. Any authenticated channel account can reach the flaw regardless of assigned permissions, and successful exploitation runs code in the OpenNMS server process.

CVSS severity8.8
High
EPSS probability3.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Java deserialization in OpenNMS Horizon and Meridian allows remote authenticated users to execute code through the ActiveMQ channel. The daemon's ActiveMQ connection factory sets trustAllPackages to true, causing object messages from channel users to be deserialized without a package allowlist. Any authenticated channel account can reach the flaw regardless of assigned permissions, and successful exploitation runs code in the OpenNMS server process.

The record

CVE
CVE-2020-12760
Published
May 11, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-502, T1210
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 11, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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