Cross-Site Request Forgery in OpenNMS Horizon

published 2021-05-20 5 y ago modified 2026-06-17 4 mo ago also GHSA-2rq5-68hm-h4j8 , EUVD-2021-0905

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; 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 `ROLE_ADMIN` 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.

Patch / fix

fixed in 3 links 2

maven org.opennms:opennms 27.1.1
opennms horizon 27.1.1
opennms meridian 2019.1.19, 2020.1.7

github.com/OpenNMS/opennms@607151e commit
github.com/OpenNMS/opennms@eb08b5e commit

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 18 mo ago (2025-04-30)

Exploit prediction

0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

whitesourcesoftware.com https://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-25931 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P
GitHub	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
maven	org.opennms:opennms	>=1.0.0, <27.1.1	27.1.1

Affected products

n/a OpenNMS

Classification

Weakness

CWE-352 Cross-Site Request Forgery

References

github.com /OpenNMS/opennms/commit/607151ea8f90212a3fb37c977fa57c7d58d26a84
web, patch, third-party-advisory
github.com /OpenNMS/opennms/commit/eb08b5ed4c5548f3e941a1f0d0363ae4439fa98c
web, patch, third-party-advisory
whitesourcesoftware.com /vulnerability-database/CVE-2021-25931
web, exploit, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2021-25931
advisory
github.com /OpenNMS/opennms
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary