CVE-2021-26084: Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability

Published Aug 30, 2021
·
Updated

Atlassian Confluence Server and Data Server contain an Object-Graph Navigation Language (OGNL) injection vulnerability that may allow an unauthenticated attacker to execute code.

Other sources

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.

Affected Software

9 affected components
Atlassian Confluence Server and Data Center
Atlassian Confluence Data Center<6.13.23
Atlassian Confluence Data Center>=6.14.0<7.4.11
Atlassian Confluence Data Center>=7.5.0<7.11.6
Atlassian Confluence Data Center>=7.12.0<7.12.5
Atlassian Confluence Server<6.13.23
Atlassian Confluence Server>=6.14.0<7.4.11
Atlassian Confluence Server>=7.5.0<7.11.6
Atlassian Confluence Server>=7.12.0<7.12.5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Atlassian Confluence Server and Data Center to a version that resolves this vulnerability.

    Fixed in 6.13.23
  2. Upgrade

    Upgrade Atlassian Confluence Server and Data Center to a version that resolves this vulnerability.

    Fixed in 7.4.11
  3. Upgrade

    Upgrade Atlassian Confluence Server and Data Center to a version that resolves this vulnerability.

    Fixed in 7.11.6
  4. Upgrade

    Upgrade Atlassian Confluence Server and Data Center to a version that resolves this vulnerability.

    Fixed in 7.12.5

Event History

Aug 30, 2021
CVE Published
via MITRE·06:30 AM
Data Sourced
via MITRE·06:30 AM
DescriptionWeakness
Data Sourced
via NVD·07:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
Nov 3, 2021
Known Exploited
via CISA·12:00 AM
Known Ransomware
via CISA·12:00 AM
Dec 15, 2025
News Published
via The Register·11:34 PM
News Published
via The Register·11:37 PM

Frequently Asked Questions

1

What is CVE-2021-26084?

CVE-2021-26084 is a vulnerability in Atlassian Confluence Server and Data Center that allows an unauthenticated attacker to execute arbitrary code.

2

How severe is CVE-2021-26084?

CVE-2021-26084 has a severity score of 9.8, which is considered critical.

3

Which versions of Confluence Server and Data Center are affected by CVE-2021-26084?

Versions before 6.13.23 and from 6.14.0 to 7.4.11 of Confluence Server and Data Center are affected by CVE-2021-26084.

4

How can an attacker exploit CVE-2021-26084?

An attacker can exploit CVE-2021-26084 by injecting malicious Object-Graph Navigation Language (OGNL) code.

5

Is there a fix for CVE-2021-26084?

Yes, updating Confluence Server and Data Center to version 7.4.11 or later will fix the vulnerability.

Contact

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