CVE-2026-21580

{
  "id": "CVE-2026-21580",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-18T22:16:50.140",
  "lastModified": "2026-11-09T20:10:00.200",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "This Critical severity Stored XSS, PrivEsc (Privilege Escalation), and Security Misconfiguration vulnerability was introduced in versions 7.1.1, 7.4.0, 7.13.0, 7.17.0, 7.19.0, 8.0.0, 8.5.0, 8.9.0, 9.0.1, 9.1.0, 9.2.0, 9.3.1, 9.4.0, 9.5.1, 10.0.2, 10.1.0 and 10.2.0 of Confluence Data Center and Server.\r\n\r\nThis Stored XSS, PrivEsc (Privilege Escalation), and Security Misconfiguration vulnerability, with a CVSS Score of 8.6, allows an unauthenticated attacker to execute arbitrary HTML or JavaScript code on a victims browser, perform actions as a higher-privileged user, and to get into the system utilizing loopholes exposed from security best-practices being overlooked.\r\n\r\nAtlassian recommends that Confluence Data Center and Server customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions:\r\n Confluence Data Center and Server 9.2: Upgrade to a release greater than or equal to 9.2.21\r\n\r\n Confluence Data Center and Server 10.2: Upgrade to a release greater than or equal to 10.2.13\r\n\r\nSee the release notes ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). You can download the latest version of Confluence Data Center and Server from the download center ([https://www.atlassian.com/software/confluence/download-archives]).\r\n\r\nThis vulnerability was reported via our Bug Bounty program."
    },
    {
      "lang": "es",
      "value": "Esta vulnerabilidad de gravedad Crítica de XSS Almacenado, PrivEsc (escalada de privilegios) y Mala Configuración de Seguridad fue introducida en las versiones 7.1.1, 7.4.0, 7.13.0, 7.17.0, 7.19.0, 8.0.0, 8.5.0, 8.9.0, 9.0.1, 9.1.0, 9.2.0, 9.3.1, 9.4.0, 9.5.1, 10.0.2, 10.1.0 y 10.2.0 de Confluence Data Center y Server.\n\nEsta vulnerabilidad de XSS Almacenado, PrivEsc (escalada de privilegios) y Mala Configuración de Seguridad, con una Puntuación CVSS de 8.6, permite a un atacante no autenticado ejecutar código HTML o JavaScript arbitrario en el navegador de una víctima, realizar acciones como un usuario con mayores privilegios y acceder al sistema utilizando lagunas expuestas por la omisión de las mejores prácticas de seguridad.\n\nAtlassian recomienda que los clientes de Confluence Data Center y Server actualicen a la última versión; si no puede hacerlo, actualice su instancia a una de las versiones fijas compatibles especificadas:\n Confluence Data Center y Server 9.2: Actualice a una versión mayor o igual a 9.2.21\n\n Confluence Data Center y Server 10.2: Actualice a una versión mayor o igual a 10.2.13\n\nConsulte las notas de la versión ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). Puede descargar la última versión de Confluence Data Center y Server desde el centro de descargas ([https://www.atlassian.com/software/confluence/download-archives]).\n\nEsta vulnerabilidad fue reportada a través de nuestro programa Bug Bounty."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Atlassian",
          "product": "Confluence Data Center",
          "versions": [
            {
              "version": "10.2.0 to 10.2.11",
              "status": "affected"
            },
            {
              "version": "10.1.0 to 10.1.2",
              "status": "affected"
            },
            {
              "version": "10.0.2 to 10.0.3",
              "status": "affected"
            },
            {
              "version": "9.5.1 to 9.5.4",
              "status": "affected"
            },
            {
              "version": "9.4.0 to 9.4.1",
              "status": "affected"
            },
            {
              "version": "9.3.1 to 9.3.2",
              "status": "affected"
            },
            {
              "version": "9.2.0 to 9.2.20",
              "status": "affected"
            },
            {
              "version": "9.1.0 to 9.1.1",
              "status": "affected"
            },
            {
              "version": "9.0.3",
              "status": "affected"
            },
            {
              "version": "8.9.6 to 8.9.8",
              "status": "affected"
            },
            {
              "version": "8.5.15 to 8.5.31",
              "status": "affected"
            },
            {
              "version": "7.19.27 to 7.19.30",
              "status": "affected"
            },
            {
              "version": "10.2.13 to 10.2.15",
              "status": "unaffected"
            },
            {
              "version": "9.2.21 to 9.2.23",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Atlassian",
          "product": "Confluence Server",
          "versions": [
            {
              "version": "8.5.15 to 8.5.31",
              "status": "affected"
            },
            {
              "version": "7.19.27 to 7.19.30",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 9.3,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-21T03:55:22.938181Z",
          "id": "CVE-2026-21580",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://confluence.atlassian.com/pages/viewpage.action?pageId=1821999768",
      "source": "[email protected]"
    },
    {
      "url": "https://jira.atlassian.com/browse/CONFSERVER-104381",
      "source": "[email protected]"
    }
  ]
}