CVE-2026-21586

Summary

CVE	CVE-2026-21586
State	PUBLISHED
Assigner	atlassian
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-09-15 17:17:11 UTC
Updated	2026-09-16 04:18:21 UTC
Description	This High severity Improper Authorization vulnerability was introduced in versions 7.4.0, 7.13.0, 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. This Improper Authorization vulnerability, with a CVSS Score of 7.1, allows an authenticated attacker to gain unintended access and can lead to the exposure of resources or functionality, possibly providing attackers with sensitive information or even execute arbitrary code. 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 9.2.24 Confluence Data Center 10.2: Upgrade to a release greater than or equal to 10.2.17 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.

Risk And Classification

Primary CVSS: v4.0 7.1 HIGH from [email protected]

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/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

Problem Types: CWE-285 | Improper Authorization | CWE-285 CWE-285 Improper Authorization

Version	Source	Type	Score	Severity	Vector
4.0	[email protected]	Secondary	7.1	HIGH	`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/C...`
4.0	CNA	DECLARED	7.1	HIGH	`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`

CVSS v4.0 Breakdown

Attack Vector

Network

Attack Complexity

Low

Attack Requirements

None

Privileges Required

Low

User Interaction

None

Confidentiality

High

Integrity

None

Availability

None

Sub Conf.

None

Sub Integrity

None

Sub Availability

None

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/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

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Atlassian	Confluence Data Center	affected 10.2.1 to 10.2.15	Not specified
CNA	Atlassian	Confluence Data Center	affected 10.1.0 to 10.1.2	Not specified
CNA	Atlassian	Confluence Data Center	affected 10.0.2 to 10.0.3	Not specified
CNA	Atlassian	Confluence Data Center	affected 9.5.1 to 9.5.4	Not specified
CNA	Atlassian	Confluence Data Center	affected 9.4.0 to 9.4.1	Not specified
CNA	Atlassian	Confluence Data Center	affected 9.3.1 to 9.3.2	Not specified
CNA	Atlassian	Confluence Data Center	affected 9.2.0 to 9.2.23	Not specified
CNA	Atlassian	Confluence Data Center	affected 9.1.1	Not specified
CNA	Atlassian	Confluence Data Center	affected 8.9.7 to 8.9.8	Not specified
CNA	Atlassian	Confluence Data Center	affected 8.5.16 to 8.5.31	Not specified
CNA	Atlassian	Confluence Data Center	affected 7.19.28 to 7.19.30	Not specified
CNA	Atlassian	Confluence Data Center	unaffected 10.2.17 to 10.2.18	Not specified
CNA	Atlassian	Confluence Data Center	unaffected 9.2.24 to 9.2.25	Not specified

References

Reference	Source	Link	Tags
jira.atlassian.com/browse/CONFSERVER-104418	[email protected]	jira.atlassian.com
confluence.atlassian.com/pages/viewpage.action	[email protected]	confluence.atlassian.com
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.