CVE-2026-19182 (GCVE-0-2026-19182)

Vulnerability from cvelistv5 – Published: 2026-08-13 04:50 – Updated: 2026-08-13 13:01
VLAI
Title
OpenNMS v2 Alarm REST API inverted authorization check lets ROLE_REST users acknowledge alarms as any user and bypass read-only
Summary
An incorrect authorization check in the v2 Alarm REST API in OpenNMS Meridian and Horizon allows a low-privileged authenticated user (ROLE_REST) to acknowledge, escalate, or clear alarms recorded as an arbitrary username, and, when also assigned ROLE_READONLY, to modify alarm state despite the read-only restriction. A credential check that should restrict these operations is guarded by an inverted condition, so it never executes for a real (non-blank) username. This can potentially allow an attacker to compromise the integrity of alarm state and audit records. 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.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 13:01 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
OpenNMS CNA under the mitre root
CNA scorecard – unranked: 7 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
The OpenNMS Group Meridian Affected: 2024.1.0 , < 2024.3.12 (maven)
Affected: 2025.0.0 , < 2025.0.9 (maven)
guessed Create a notification for this product.
The OpenNMS Group Horizon Affected: 36.0.0 , < 36.0.3 (maven)
guessed Create a notification for this product.
Credits
Santosh Kumar Puppala
Show details on NVD website
To clipboard 

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