CVE-2026-21580
CriticalCVSS 9.3Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
A Critical Stored XSS, Privilege Escalation, and Security Misconfiguration vulnerability in Confluence Data Center and Server allows an unauthenticated attacker to execute arbitrary HTML or JavaScript in a victim's browser, perform actions as a higher-privileged user, and exploit security best-practice oversights.
Risk Assessment
An attacker could compromise user accounts, escalate privileges, and gain unauthorized access to the system, potentially leading to data breaches and integrity loss.
Recommendation
Upgrade Confluence Data Center and Server to version 9.2.21 or later (for 9.2) and 10.2.13 or later (for 10.2). If possible, apply the latest available version.
Other vulnerabilities in Confluence Data Center and Server
See all- CVE-2023-22527CriticalActively exploited
A template injection vulnerability on older versions of Confluence Data Center and Server allows an unauthenticated attacker to achieve RCE on an affected instance. Customers using an affected version must take immediate action.
- CVE-2023-22518CriticalActively exploited
All versions of Confluence Data Center and Server are affected by this unexploited vulnerability. This Improper Authorization vulnerability allows an unauthenticated attacker to reset Confluence and create a Confluence instance administrator account. Using this account, an attacker can then perform all administrative actions that are available to Confluence instance administrator leading to - but not limited to - full loss of confidentiality, integrity and availability.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS