Cross-Site Request Forgery in OpenNMS Horizon

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

• CVE-2021-25931: 0.73% estimated exploitation activity in the next 30 days; percentile 54.15 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.1; OpenNMS Meridian, versions meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1; meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1 are vulnerable to CSRF, due to no CSRF protection at /opennms/admin/userGroupView/users/updateUser. This flaw allows assigning ROLEADMIN security role to a normal user. Using this flaw, an attacker can trick the admin user to assign administrator privileges to a normal user by enticing him to click upon an attacker-controlled website.

Published by the source

25 May 2021, 18:46 UTC

Last modified by the source

1 May 2025, 00:21 UTC

Source last checked

26 Oct 2026, 16:35 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-2rq5-68hm-h4j8

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# Patch Next advisory brief: CVE-2021-25931

Advisory: Cross-Site Request Forgery in OpenNMS Horizon
IDs: CVE-2021-25931, GHSA-2rq5-68hm-h4j8
Record: https://patchnext.com/advisories/cve-2021-25931 (revision 1, source checked 26 Oct 2026, 16:35 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.opennms:opennms 27.1.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.opennms:opennms: affected >= 1.0.0, < 27.1.1; fixed in 27.1.1

## Suggested inspection (read-only)
- Maven org.opennms:opennms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.opennms:opennms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-2rq5-68hm-h4j8 (GitHub-reviewed advisory GHSA-2rq5-68hm-h4j8 lists affected ranges: Maven org.opennms:opennms >=1.0.0 <27.1.1)

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