CVE-2026-19135
OpenNMS JEXL sandbox bypass in Measurements REST API allows ROLE_USER to load arbitrary classes
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.
INFO
Published Date :
Aug. 13, 2026, 5:17 a.m.
Last Modified :
Aug. 13, 2026, 5:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 70b007e9-5235-4ee5-90b5-a71a81beeda0 | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Upgrade OpenNMS to Meridian 2024.3.12 or later.
- Upgrade OpenNMS to Horizon 36.0.3 or later.
- Ensure OpenNMS is not directly accessible from the Internet.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-19135.
| URL | Resource |
|---|---|
| https://github.com/OpenNMS/opennms/pull/8754 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-19135 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-19135
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-19135 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-19135 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 13, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/OpenNMS', 'vendor': 'The OpenNMS Group', 'product': 'Meridian', 'versions': [{'status': 'affected', 'version': '2024.1.0', 'lessThan': '2024.3.12', 'versionType': 'maven'}, {'status': 'affected', 'version': '2025.0.0', 'lessThan': '2025.0.9', 'versionType': 'maven'}], 'defaultStatus': 'unaffected'}, {'repo': 'https://github.com/OpenNMS', 'vendor': 'The OpenNMS Group', 'product': 'Horizon', 'versions': [{'status': 'affected', 'version': '36.0.0', 'lessThan': '36.0.3', 'versionType': 'maven'}], 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Added CWE CWE-470 Added Reference https://github.com/OpenNMS/opennms/pull/8754