CVE-2021-26084

9.8 CRITICAL CISA KEV - Actively Exploited

Published: August 30, 2021 Modified: October 24, 2025

Description

In affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that would allow an unauthenticated attacker to execute arbitrary code on a Confluence Server or Data Center instance. The affected versions are before version 6.13.23, from version 6.14.0 before 7.4.11, from version 7.5.0 before 7.11.6, and from version 7.12.0 before 7.12.5.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0

Vector String

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory

http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html

Source: security@atlassian.com

Exploit Third Party Advisory VDB Entry

https://jira.atlassian.com/browse/CONFSERVER-67940

Source: security@atlassian.com

Issue Tracking Patch Vendor Advisory

http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html

Source: af854a3a-2127-422b-91ae-364da2661108

Exploit Third Party Advisory VDB Entry

https://jira.atlassian.com/browse/CONFSERVER-67940

Source: af854a3a-2127-422b-91ae-364da2661108

Issue Tracking Patch Vendor Advisory

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26084

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

US Government Resource

5 reference(s) from NVD

Quick Stats

CVSS v3 Score

9.8 / 10.0

EPSS (Exploit Probability)

94.4%

100th percentile

Exploitation Status

Actively Exploited

Remediation due: 2021-11-17

Weaknesses (CWE)

CWE-917 CWE-917

Affected Vendors

atlassian

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