CVE-2026-21577

Published Jul 21, 2026 CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Title Authenticated Resource Exhaustion DoS in Atlassian Confluence Data Center
Type Values Removed Values Added
Title Authenticated Resource Exhaustion DoS in Atlassian Confluence Data Center
Type Values Removed Values Added
Title High Severity Denial of Service in Atlassian Confluence Data Center
Type Values Removed Values Added
Title High Severity Denial of Service in Atlassian Confluence Data Center
Type Values Removed Values Added
Weaknesses CWE-400
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
First Time appeared Atlassian
Atlassian confluence Data Center
CPEs cpe:2.3:a:atlassian:confluence_data_center:*:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.10:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.11:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.12:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.13:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.14:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.15:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.17:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.18:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.19:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.20:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.21:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.22:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.2:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.3:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.4:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.5:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.6:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.7:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.8:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.2.9:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_data_center:9.4.1:*:*:*:*:*:*:*
Vendors & Products Atlassian
Atlassian confluence Data Center
References
Metrics cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
atlassian
Published
Updated
Jul 22, 2026, 6:48 PM
Reserved
Jan 1, 2026, 12:00 AM
Status
Analyzed
Published
Jul 21, 2026, 6:16 PM
Modified
Oct 24, 2026, 7:10 PM