Advisory severityCritical9.8Atlassian Exploited CISA KEV

Critical [CVE-2021-26084] In affected versions of Confluence Server and Data Center, an OGNL injection vulnerability exists that would

This critical-severity Atlassian advisory covers CVE-2021-26084; related products: Confluence Server.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2021-26084 Source published Aug 30, 2021Source updated Jun 17, 2026

VulniPulse record published Aug 30, 2021Record updated Jun 17, 2026

CVE-2021-26084

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Summary

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.

CISA Known Exploited Vulnerability

Listed:: Nov 3, 2021 · federal remediation due Nov 17, 2021
Required action:: Apply updates per vendor instructions.
Ransomware use:: Known ransomware campaign use, according to CISA

KEV is a prioritization signal from CISA — remediation detail still comes from the vendor advisory.

Affected versions

6.14.0
7.5.0
7.12.0

Official advisory · high-confidence parse· fetched 3 months ago·verify at source

Fixed versions

7.4.11
7.11.6
7.12.5

Official advisory · high-confidence parse· fetched 3 months ago·verify at source

Mitigation

Upgrade to a fixed release: 7.4.11, 7.11.6, 7.12.5. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 3 months ago·verify at source

Discussion(0)

No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.