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: 5 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 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-19182",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-13T13:01:50.881107Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-13T13:01:57.556Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Meridian",
          "repo": "https://github.com/OpenNMS",
          "vendor": "The OpenNMS Group",
          "versions": [
            {
              "lessThan": "2024.3.12",
              "status": "affected",
              "version": "2024.1.0",
              "versionType": "maven"
            },
            {
              "lessThan": "2025.0.9",
              "status": "affected",
              "version": "2025.0.0",
              "versionType": "maven"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "Horizon",
          "repo": "https://github.com/OpenNMS",
          "vendor": "The OpenNMS Group",
          "versions": [
            {
              "lessThan": "36.0.3",
              "status": "affected",
              "version": "36.0.0",
              "versionType": "maven"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Santosh Kumar Puppala"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eAn 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.\u003c/p\u003e\u003cp\u003eThe 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\u0027s private networks and should not be directly accessible from the Internet.\u003c/p\u003e"
            }
          ],
          "value": "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.\n\n\n\nThe 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\u0027s private networks and should not be directly accessible from the Internet."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-863",
              "description": "CWE-863 Incorrect Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-13T04:50:39.638Z",
        "orgId": "70b007e9-5235-4ee5-90b5-a71a81beeda0",
        "shortName": "OpenNMS"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/OpenNMS/opennms/pull/8755"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eUpgrade to Meridian 2024.3.12, 2025.0.9 and Horizon 36.0.3 or newer.\u003c/p\u003e"
            }
          ],
          "value": "Upgrade to Meridian 2024.3.12, 2025.0.9 and Horizon 36.0.3 or newer."
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "OpenNMS v2 Alarm REST API inverted authorization check lets ROLE_REST users acknowledge alarms as any user and bypass read-only",
      "x_generator": {
        "engine": "Vulnogram 1.0.4"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "70b007e9-5235-4ee5-90b5-a71a81beeda0",
    "assignerShortName": "OpenNMS",
    "cveId": "CVE-2026-19182",
    "datePublished": "2026-08-13T04:50:39.638Z",
    "dateReserved": "2026-08-06T18:03:49.526Z",
    "dateUpdated": "2026-08-13T13:01:57.556Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-19182",
      "date": "2026-10-14",
      "epss": "0.00254",
      "percentile": "0.15784"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Meridian",
                "repo": "https://github.com/OpenNMS",
                "vendor": "The OpenNMS Group",
                "versions": [
                  {
                    "lessThan": "2024.3.12",
                    "status": "affected",
                    "version": "2024.1.0",
                    "versionType": "maven"
                  },
                  {
                    "lessThan": "2025.0.9",
                    "status": "affected",
                    "version": "2025.0.0",
                    "versionType": "maven"
                  }
                ]
              },
              {
                "defaultStatus": "unaffected",
                "product": "Horizon",
                "repo": "https://github.com/OpenNMS",
                "vendor": "The OpenNMS Group",
                "versions": [
                  {
                    "lessThan": "36.0.3",
                    "status": "affected",
                    "version": "36.0.0",
                    "versionType": "maven"
                  }
                ]
              }
            ],
            "source": "security@opennms.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "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.\n\n\n\nThe 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\u0027s private networks and should not be directly accessible from the Internet."
          }
        ],
        "id": "CVE-2026-19182",
        "lastModified": "2026-09-08T19:20:25.117",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 4.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "LOW",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 1.4,
              "source": "security@opennms.com",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-19182",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-13T13:01:50.881107Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-08-13T05:17:22.893",
        "references": [
          {
            "source": "security@opennms.com",
            "url": "https://github.com/OpenNMS/opennms/pull/8755"
          }
        ],
        "sourceIdentifier": "security@opennms.com",
        "vulnStatus": "Awaiting Analysis",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-863"
              }
            ],
            "source": "security@opennms.com",
            "type": "Secondary"
          }
        ]
      }
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.