CVEs / CVE-2021-26084
CVE-2021-26084: Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 99.9% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Atlassian Confluence Server and Data Server contain an Object-Graph Navigation Language (OGNL) injection vulnerability that may allow an unauthenticated attacker to execute code.
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Atlassian Confluence Server | from unspecified, before 6.13.23 | 6.13.23 |
| Atlassian Confluence Server | from 6.14.0, before unspecified | unspecified |
| Atlassian Confluence Server | from unspecified, before 7.4.11 | 7.4.11 |
| Atlassian Confluence Server | from 7.5.0, before unspecified | unspecified |
| Atlassian Confluence Server | from unspecified, before 7.11.6 | 7.11.6 |
| Atlassian Confluence Server | from 7.12.0, before unspecified | unspecified |
| Atlassian Confluence Server | from unspecified, before 7.12.5 | 7.12.5 |
| Atlassian Confluence Data Center | from unspecified, before 6.13.23 | 6.13.23 |
| Atlassian Confluence Data Center | from 6.14.0, before unspecified | unspecified |
| Atlassian Confluence Data Center | from unspecified, before 7.4.11 | 7.4.11 |
| Atlassian Confluence Data Center | from 7.5.0, before unspecified | unspecified |
| Atlassian Confluence Data Center | from unspecified, before 7.11.6 | 7.11.6 |
| Atlassian Confluence Data Center | from 7.12.0, before unspecified | unspecified |
| Atlassian Confluence Data Center | from unspecified, before 7.12.5 | 7.12.5 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Known |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-917 |
References
- CVE-2021-26084 on NVD
- CVE-2021-26084 in the CISA KEV catalog
- http://packetstormsecurity.com/files/167449/Atlassian-Confluence-Namespace-OGNL-Injection.html Exploit, Third Party Advisory, VDB Entry
- https://jira.atlassian.com/browse/CONFSERVER-67940 Issue Tracking, Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26084 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.