CVE-2021-26084

CriticalCVSS 9.8/10Known exploited (CISA KEV)Last modified Jun 17, 2026

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.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Aug 30, 2021
Last modified
Jun 17, 2026
Added to CISA KEV
Nov 3, 2021
NVD status
Analyzed

Related CVEs from 2021

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CVE-2021-26084: Critical severity, CVSS 9.8 | Vulnix