VulnerabilityAwaiting Analysis

CVE-2026-19135

A JEXL expression sandbox bypass exists in multiple versions of OpenNMS Meridian and Horizon.

MEDIUM 5.4EPSS 0.17%

Does this matter?

Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.

Description

A JEXL expression sandbox bypass exists in multiple versions of OpenNMS Meridian and Horizon. A low-privileged authenticated user can submit a crafted expression to the Measurements REST API that escapes the sandbox and loads arbitrary Java classes on the server. This can potentially allow an attacker to gain access to confidential information and compromise integrity. The solution is to upgrade to Meridian 2024.3.12, 2025.0.9 and Horizon 36.0.3 or newer. Meridian and Horizon installation instructions state that they are intended for installation within an organization's private networks and should not be directly accessible from the Internet.

CVSS 3.1: 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
EPSS: 0.17% probability · 7th percentile
CISA KEV: Not listed
Weakness: CWE-470
Source: security@opennms.com

References

https://github.com/OpenNMS/opennms/pull/8754

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.