Vulnerability-Lookup

ubuntu-cve-2026-48551

Vulnerability from osv_ubuntu

Published

2026-08-13 00:00

Modified

2026-08-13 00:00

Summary

Details

Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 contain a cross-site request forgery protection bypass via a self-supplied double-submit cookie. An attacker can supply matching cookie and request parameter values to bypass CSRF protection, enabling unauthenticated attackers to run commands as authorized users via malicious links.

Severity

7.4 (High)


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

6.1 (Medium)


                    
                      CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-48551	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-48551	REPORT
	https://github.com/NagiosEnterprises/nagioscore/b…	REPORT
	https://www.nagios.com/security-disclosures/nagio…	REPORT
	https://www.vulncheck.com/advisories/nagios-core-…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nagios4",
            "binary_version": "4.3.4-3ubuntu0.1"
          },
          {
            "binary_name": "nagios4-cgi",
            "binary_version": "4.3.4-3ubuntu0.1"
          },
          {
            "binary_name": "nagios4-common",
            "binary_version": "4.3.4-3ubuntu0.1"
          },
          {
            "binary_name": "nagios4-core",
            "binary_version": "4.3.4-3ubuntu0.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "nagios4",
        "purl": "pkg:deb/ubuntu/nagios4@4.3.4-3ubuntu0.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.3.4-3",
        "4.3.4-3ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nagios4",
            "binary_version": "4.4.6-4ubuntu0.22.04.1"
          },
          {
            "binary_name": "nagios4-cgi",
            "binary_version": "4.4.6-4ubuntu0.22.04.1"
          },
          {
            "binary_name": "nagios4-common",
            "binary_version": "4.4.6-4ubuntu0.22.04.1"
          },
          {
            "binary_name": "nagios4-core",
            "binary_version": "4.4.6-4ubuntu0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "nagios4",
        "purl": "pkg:deb/ubuntu/nagios4@4.4.6-4ubuntu0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.4.6-4",
        "4.4.6-4ubuntu0.22.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nagios4",
            "binary_version": "4.4.6-4ubuntu0.24.04.1"
          },
          {
            "binary_name": "nagios4-cgi",
            "binary_version": "4.4.6-4ubuntu0.24.04.1"
          },
          {
            "binary_name": "nagios4-common",
            "binary_version": "4.4.6-4ubuntu0.24.04.1"
          },
          {
            "binary_name": "nagios4-core",
            "binary_version": "4.4.6-4ubuntu0.24.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "nagios4",
        "purl": "pkg:deb/ubuntu/nagios4@4.4.6-4ubuntu0.24.04.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.4.6-4",
        "4.4.6-4ubuntu0.24.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nagios4",
            "binary_version": "4.4.6-4.1ubuntu2"
          },
          {
            "binary_name": "nagios4-cgi",
            "binary_version": "4.4.6-4.1ubuntu2"
          },
          {
            "binary_name": "nagios4-common",
            "binary_version": "4.4.6-4.1ubuntu2"
          },
          {
            "binary_name": "nagios4-core",
            "binary_version": "4.4.6-4.1ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "nagios4",
        "purl": "pkg:deb/ubuntu/nagios4@4.4.6-4.1ubuntu2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.4.6-4.1ubuntu1",
        "4.4.6-4.1ubuntu2"
      ]
    }
  ],
  "aliases": [],
  "details": "Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 contain a cross-site request forgery protection bypass via a self-supplied double-submit cookie. An attacker can supply matching cookie and request parameter values to bypass CSRF protection, enabling unauthenticated attackers to run commands as authorized users via malicious links.",
  "id": "UBUNTU-CVE-2026-48551",
  "modified": "2026-08-13T00:00:00Z",
  "published": "2026-08-13T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-48551"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-48551"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog"
    },
    {
      "type": "REPORT",
      "url": "https://www.nagios.com/security-disclosures/nagios-core/"
    },
    {
      "type": "REPORT",
      "url": "https://www.vulncheck.com/advisories/nagios-core-xi-csrf-protection-bypass-via-double-submit-cookie"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-48551"
  ]
}

CVE-2026-48551 (GCVE-0-2026-48551)

Vulnerability from cvelistv5 – Published: 2026-08-12 16:32 – Updated: 2026-08-14 16:49

Title

Nagios Core / XI CSRF Protection Bypass via Double-Submit Cookie

Summary

Severity

6.1 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N

7.4 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-13 16:25 UTC

CWE

CWE-352 - Cross-Site Request Forgery (CSRF)

Assigner

VulnCheck

References

3 references

URL	Tags
https://www.nagios.com/security-disclosures/nagio…	vendor-advisorypatch
https://github.com/NagiosEnterprises/nagioscore/b…	release-notes
https://www.vulncheck.com/advisories/nagios-core-…	third-party-advisory

Impacted products

2 products

Vendor	Product	Version
Nagios Enterprises, LLC.	Nagios Core	Affected: 0 , < 4.5.14 (semver)
Nagios Enterprises, LLC.	Nagios XI	Affected: 0 , < 2026R1.7 (custom)

Date Public

2026-08-05 00:00

Credits

Zach Hanley of Horizon3.ai

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48551",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-13T16:25:52.275559Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-13T16:26:01.041Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "Nagios Core",
          "vendor": "Nagios Enterprises, LLC.",
          "versions": [
            {
              "lessThan": "4.5.14",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Nagios XI",
          "vendor": "Nagios Enterprises, LLC.",
          "versions": [
            {
              "lessThan": "2026R1.7",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:nagios:nagios_core:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.5.14",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:nagios:nagios_xi:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "2026r1.7",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Zach Hanley of Horizon3.ai"
        }
      ],
      "datePublic": "2026-08-05T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 contain a cross-site request forgery protection bypass via a self-supplied double-submit cookie. An attacker can supply matching cookie and request parameter values to bypass CSRF protection, enabling unauthenticated attackers to run commands as authorized users via malicious links."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-352",
              "description": "Cross-Site Request Forgery (CSRF)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-14T16:49:59.206Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Security Disclosures",
          "tags": [
            "vendor-advisory",
            "patch"
          ],
          "url": "https://www.nagios.com/security-disclosures/nagios-core/"
        },
        {
          "name": "Changelog",
          "tags": [
            "release-notes"
          ],
          "url": "https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/nagios-core-xi-csrf-protection-bypass-via-double-submit-cookie"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Nagios Core / XI CSRF Protection Bypass via Double-Submit Cookie",
      "x_generator": {
        "engine": "vulncheck"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-48551",
    "datePublished": "2026-08-12T16:32:16.601Z",
    "dateReserved": "2026-05-21T18:34:46.418Z",
    "dateUpdated": "2026-08-14T16:49:59.206Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

ubuntu-cve-2026-48551

Vulnerability from osv_ubuntu

CVE-2026-48551 (GCVE-0-2026-48551)

Tags

Sightings

Nomenclature