CVE-2026-21577
Full vulnerability record from the local CVENow database.
Description
This High severity DoS (Denial of Service) vulnerability was introduced in versions 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. This DoS (Denial of Service) vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Atlassian recommends that Confluence Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: Confluence Data Center 9.2: Upgrade to a release greater than or equal to 9.2.17 Confluence Data Center 10.2: Upgrade to a release greater than or equal to 10.2.7 See the release notes ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). You can download the latest version of Confluence Data Center from the download center ([https://www.atlassian.com/software/confluence/download-archives]). This vulnerability was reported via our Penetration Testing program.
Severity
HIGH
CVSS score
7.1
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-21 18:16:57.327000
Last modified
2026-10-24 19:10:00.127000
View original CVE JSON
{
"id": "CVE-2026-21577",
"sourceIdentifier": "[email protected]",
"published": "2026-07-21T18:16:57.327",
"lastModified": "2026-10-24T19:10:00.127",
"vulnStatus": "Analyzed",
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"value": "This High severity DoS (Denial of Service) vulnerability was introduced in versions 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.\r\n\r\nThis DoS (Denial of Service) vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network.\r\n\r\nAtlassian recommends that Confluence Data Center 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 9.2: Upgrade to a release greater than or equal to 9.2.17\r\n\r\n Confluence Data Center 10.2: Upgrade to a release greater than or equal to 10.2.7\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 from the download center ([https://www.atlassian.com/software/confluence/download-archives]).\r\n\r\nThis vulnerability was reported via our Penetration Testing program."
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"lang": "es",
"value": "Esta vulnerabilidad DoS (denegación de servicio) de alta gravedad se introdujo en las versiones 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.\n\nEsta vulnerabilidad DoS (denegación de servicio), con una puntuación CVSS de 7.1, permite a un atacante autenticado hacer que un recurso no esté disponible para sus usuarios previstos al interrumpir temporal o indefinidamente los servicios de un host conectado a una red.\n\nAtlassian recomienda que los clientes de Confluence Data Center actualicen a la última versión; si no puede hacerlo, actualice su instancia a una de las versiones fijas compatibles especificadas:\n Confluence Data Center 9.2: Actualice a una versión mayor o igual a 9.2.17\n\n Confluence Data Center 10.2: Actualice a una versión mayor o igual a 10.2.7\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 desde el centro de descargas ([https://www.atlassian.com/software/confluence/download-archives]).\n\nEsta vulnerabilidad fue reportada a través de nuestro programa de pruebas de penetración."
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"source": "[email protected]",
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"source": "[email protected]",
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}