CVE-2026-21577

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.

CVSS

No CVSS.

References

Link	Resource
https://confluence.atlassian.com/pages/viewpage.action?pageId=1821999345
https://jira.atlassian.com/browse/CONFSERVER-104334

Configurations

No configuration.

History

22 Jul 2026, 19:16

Type	Values Removed	Values Added
CWE		CWE-400

21 Jul 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-21 18:16

Updated : 2026-07-22 19:16

NVD link : CVE-2026-21577

Mitre link : CVE-2026-21577

CVE.ORG link : CVE-2026-21577

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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