CVE-2026-21580 - Vulnerability Details

- Stored XSS, Privilege Escalation, and Security Misconfiguration in Atlassian Confluence

Description

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.

This 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.

Atlassian 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:
Confluence Data Center and Server 9.2: Upgrade to a release greater than or equal to 9.2.21

Confluence Data Center and Server 10.2: Upgrade to a release greater than or equal to 10.2.13

See 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]).

This vulnerability was reported via our Bug Bounty program.

Published: 2026-08-18

Score: 8.6 High

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Atlassian

Confluence Data Center

affected

Version	Status	Constraints
`10.2.0 to 10.2.11`	affected	—
`10.1.0 to 10.1.2`	affected	—
`10.0.2 to 10.0.3`	affected	—
`9.5.1 to 9.5.4`	affected	—
`9.4.0 to 9.4.1`	affected	—
`9.3.1 to 9.3.2`	affected	—
`9.2.0 to 9.2.20`	affected	—
`9.1.0 to 9.1.1`	affected	—
`9.0.3`	affected	—
`8.9.6 to 8.9.8`	affected	—
`8.5.15 to 8.5.31`	affected	—
`7.19.27 to 7.19.30`	affected	—
`10.2.13 to 10.2.15`	unaffected	—
`9.2.21 to 9.2.23`	unaffected	—

Atlassian

Confluence Server

affected

Version	Status	Constraints
`8.5.15 to 8.5.31`	affected	—
`7.19.27 to 7.19.30`	affected	—

No data.

Vendor Product Confidence Versions

Atlassian

Confluence Data Center

95%

Version	Status	Scheme	Platform
`[10.2.0,10.2.11]`	affected	semver	—
`[10.1.0,10.1.2]`	affected	semver	—
`[10.0.2,10.0.3]`	affected	semver	—
`[9.5.1,9.5.4]`	affected	semver	—
`[9.4.0,9.4.1]`	affected	semver	—
`[9.3.1,9.3.2]`	affected	semver	—
`[9.2.0,9.2.20]`	affected	semver	—
`[9.1.0,9.1.1]`	affected	semver	—
`9.0.3`	affected	semver	—
`[8.9.6,8.9.8]`	affected	semver	—
`[8.5.15,8.5.31]`	affected	semver	—
`[7.19.27,7.19.30]`	affected	semver	—
`[10.2.13,10.2.15]`	unaffected	semver	—
`[9.2.21,9.2.23]`	unaffected	semver	—

Atlassian

Confluence Server

95%

Version	Status	Scheme	Platform
`[8.5.15,8.5.31]`	affected	semver	—
`[7.19.27,7.19.30]`	affected	semver	—

Found an issue or want to improve our Enrichment? You can suggest it directly by opening an issue on our dedicated GitHub repository .

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00395.

Exploitation none

Automatable yes

Technical Impact total

References

Link	Providers
https://confluence.atlassian.com/pages/viewpage.action?pageId=1821999768
https://jira.atlassian.com/browse/CONFSERVER-104381

History

Fri, 21 Aug 2026 05:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Wed, 19 Aug 2026 09:00:00 +0000

Type	Values Removed	Values Added
Title		Stored XSS, Privilege Escalation, and Security Misconfiguration in Atlassian Confluence
Weaknesses		CWE-269 CWE-710 CWE-79

Tue, 18 Aug 2026 22:15:00 +0000

Type	Values Removed	Values Added
Description		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. This 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. Atlassian 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: Confluence Data Center and Server 9.2: Upgrade to a release greater than or equal to 9.2.21 Confluence Data Center and Server 10.2: Upgrade to a release greater than or equal to 10.2.13 See 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]). This vulnerability was reported via our Bug Bounty program.
First Time appeared		Atlassian Atlassian confluence Data Center Atlassian confluence Server
CPEs		cpe:2.3:a:atlassian:confluence_data_center:::::::: cpe:2.3:a:atlassian:confluence_data_center:8.5.22:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.23:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.24:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.25:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.26:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.27:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.28:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.29:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.30:::::::* cpe:2.3:a:atlassian:confluence_data_center:8.5.31:::::::* cpe:2.3:a:atlassian:confluence_data_center:9.0.3:::::::* 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:9.2.16:::::::* 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:9.2.23:::::::* 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:::::::* cpe:2.3:a:atlassian:confluence_server:::::::: cpe:2.3:a:atlassian:confluence_server:8.5.22:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.23:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.24:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.25:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.26:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.27:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.28:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.29:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.30:::::::* cpe:2.3:a:atlassian:confluence_server:8.5.31:::::::*
Vendors & Products		Atlassian Atlassian confluence Data Center Atlassian confluence Server
References		https://confluence.atlassian.com/pages/viewpage.action?pageId=1821999768 https://jira.atlassian.com/browse/CONFSERVER-104381
Metrics		cvssV4_0 `{'score': 8.6, 'vector': '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'}`

Subscriptions

Atlassian Confluence Data Center Confluence Server

MITRE

Status: PUBLISHED

Assigner: atlassian

Published: 2026-08-18T22:00:00.396Z

Updated: 2026-08-21T14:45:07.562Z

Reserved: 2026-01-01T00:00:40.721Z

Link: CVE-2026-21580

Vulnrichment

Updated: 2026-08-20T15:26:54.524Z

NVD

Status : Awaiting Analysis

Published: 2026-08-18T22:16:50.140

Modified: 2026-08-26T16:46:22.330

Link: CVE-2026-21580

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-08-19T11:00:04Z

Weaknesses

Tracking

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Exploitation none

Automatable yes

Technical Impact total

Subscriptions

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