How severe is CVE-2021-26084?

CVE-2021-26084 has a CVSS 3.1 base score of 9.8 (CRITICAL). EPSS estimates a 100.0% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-26084: Atlassian Confluence Server and Data Center

CISA Known Exploited Vulnerabilities

Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2021-11-03

Remediation due

2021-11-17

Ransomware

Known use

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-26084

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.

Severity

CVSS 3.1 · CISA9.8 CRITICAL

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

SSVC · CISA-ADP

Exploitationactive

Automatableyes

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
Atlassian	Confluence Server	unspecified to <6.13.23 6.14.0 to <unspecified unspecified to <7.4.11 7.5.0 to <unspecified unspecified to <7.11.6 7.12.0 to <unspecified unspecified to <7.12.5
Atlassian	Confluence Data Center	unspecified to <6.13.23 6.14.0 to <unspecified unspecified to <7.4.11 7.5.0 to <unspecified unspecified to <7.11.6 7.12.0 to <unspecified unspecified to <7.12.5

References

2 Links

Other references

Record Details

Published

2021-08-30

Last updated

2025-12-16

Assigner (CNA)

atlassian

Credited to

More from Atlassian

CVE-2023-2251810

Atlassian Confluence Data Center and Server Improper Authorization Vulnerability

CVE-2022-261349.8

Atlassian Confluence Server and Data Center Remote Code Execution Vulnerability

CVE-2021-260865.3

Atlassian Jira Server and Data Center Path Traversal Vulnerability

CVE-2023-2252710

Atlassian Confluence Data Center and Server Template Injection Vulnerability

CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.