How severe is CVE-2020-12760?

CVE-2020-12760 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-12760 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12760?

CVE-2020-12760 primarily affects Opennms Opennms Horizon. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-12760?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-12760 published?

CVE-2020-12760 was published on 2020-05-11 and last updated on 2026-06-17.

CVE-2020-12760

CVE-2020-12760 is a high-severity vulnerability in Opennms Opennms Horizon with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 3% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Opennms Opennms Horizon
Published: 2020-05-11
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2020-12760?: 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.
How severe is CVE-2020-12760?: CVE-2020-12760 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-12760 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12760?: CVE-2020-12760 primarily affects Opennms Opennms Horizon. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-12760?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-12760 published?: CVE-2020-12760 was published on 2020-05-11 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:opennms:opennms_horizon:*:*:*:*:*:*:*:*
cpe:2.3:a:opennms:opennms_meridian:*:*:*:*:*:*:*:*

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