Nagios Core / XI CSRF via cmd.cgi Double-Submit Cookie

{
  "id": "27e7b03448c3adef889e5e40f5be0b5b6e7bb57f03fdf37403cabfb352fe2520",
  "url": "https://osv.dev/vulnerability/CVE-2026-48549",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Nagios Core / XI CSRF via cmd.cgi Double-Submit Cookie",
    "summary": "Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 contains a CSRF vulnerability in cmd.cgi. When no Cookie header is present, the double-submit cookie protection can be bypassed by supplying matching NagFormId and nagFormId values in the POST body, allowing a cross-site request to execute Nagios commands as a currently authenticated user.",
    "evidence": "osv:CVE-2026-48549",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-48549",
      "aliases": [
        "CVE-2026-48549"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/nagiosenterprises/nagioscore",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "367ec800bfbecf1ca1e857fe73bdb5fba5cc9003"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.5.13"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.5.13"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "nagios-4.5.12",
            "nagios-4.5.11",
            "nagios-4.5.10",
            "nagios-4.5.9",
            "nagios-4.5.8",
            "nagios-4.5.7",
            "nagios-4.5.6",
            "nagios-4.5.5",
            "nagios-4.5.4",
            "nagios-4.5.3",
            "nagios-4.5.2",
            "nagios-4.5.1",
            "nagios-4.5.0",
            "nagios-4.4.14",
            "nagios-4.4.13",
            "nagios-4.4.12",
            "nagios-4.4.11",
            "nagios-4.4.10",
            "nagios-4.4.9",
            "nagios-4.4.8",
            "nagios-4.4.7",
            "nagios-4.4.6",
            "nagios-4.4.5",
            "nagios-4.4.4",
            "nagios-4.4.3",
            "nagios-4.4.3rc1",
            "nagios-4.4.1",
            "nagios-4.4.0",
            "nagios-4.3.4",
            "nagios-4.3.3",
            "nagios-4.3.2",
            "nagios-4.3.1",
            "release-4.3.0",
            "nagios-4.3.0",
            "release-4.2.4",
            "nagios-4.2.2",
            "4.2.1",
            "nagios-4.1.1",
            "nagios-4.1.0",
            "nagios-4.1.0rc2",
            "nagios-4.0.6",
            "nagios-4.0.5",
            "nagios-4.0.4",
            "nagios-4.0.0",
            "nagios-4.0.0-beta4",
            "nagios-4.0.0-beta3",
            "nagios-4.0.0-beta2",
            "nagios-4.0.0-beta1",
            "nagios-3.4.1",
            "nagios-3.4.0",
            "nagios-3.3.1",
            "nagios-3.2.3",
            "nagios-3.2.2",
            "nagios-3.2.1",
            "nagios-3.2.0",
            "nagios-3.1.2",
            "nagios-3.1.1",
            "nagios-3.1.0",
            "nagios-3.0.6",
            "nagios-3.0.5",
            "nagios-3.0.4",
            "nagios-3.0.3",
            "nagios-3.0.2",
            "nagios-3.0.1",
            "nagios-3.0",
            "nagios-3.0rc3",
            "nagios-3.0rc2",
            "nagios-3.0rc1",
            "nagios-3.0b7",
            "nagios-3.0b6",
            "nagios-3.0b5",
            "nagios-3.0b4",
            "nagios-3.0b3",
            "nagios-3.0b2",
            "nagios-3.0b1",
            "nagios-3.0a5",
            "nagios-3.0a4",
            "nagios-3.0a3",
            "nagios-3.0a2",
            "nagios-3.0a1",
            "nagios-2.0",
            "nagios-2.0rc1",
            "nagios-2.0b6",
            "nagios-2.0.b5",
            "nagios-2.0b4",
            "nagios-2.0b3",
            "nagios-2.0b2",
            "nagios-2.0b1",
            "nagios-1.0b6",
            "nagios-1.0b5",
            "nagios-1.0b4",
            "nagios-1.0b3",
            "nagios-1.0b2",
            "nagios-1.0b1",
            "nagios-1.0a7",
            "nagios-1.0a6"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-48549.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.792152095Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48549.json",
        "https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-48549",
        "https://www.vulncheck.com/advisories/nagios-core-xi-csrf-via-cmd-cgi-double-submit-cookie",
        "https://www.nagios.com/security-disclosures/nagios-core/"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-352"
        ],
        "cna_assigner": "VulnCheck",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "2026R1.5"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48549.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-48549",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 490090,
  "published_at": "2026-08-26T15:37:20.083+00:00"
}