RCE in Atlassian Confluence Data Center
CVE-2021-26084
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.
Vulnerability class: Log4Shell (CVE-2021-44228)
EPSS: 1.000 (100.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Atlassian Confluence Data Center — versions unspecified, 6.14.0, 7.5.0
- Atlassian Confluence_data_center
- Atlassian Confluence Server — versions unspecified, 6.14.0, 7.5.0
- Atlassian Confluence_server
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
Required action: Apply updates per vendor instructions.
Known ransomware campaign use: yes.
Public proof-of-concept exploits
References
- security@atlassian.com (Patch, x_refsource_MISC, Issue Tracking, Vendor Advisory)
- security@atlassian.com (Exploit, VDB Entry, Third Party Advisory, x_refsource_MISC)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2021-26084?
- CVE-2021-26084 is a critical-severity vulnerability in Atlassian Confluence Data Center, classified under Improper Neutralization of Special Elements used in an Expression Language Statement (Expression Language Injection). CVSS score: 9.8/10. Published 2021-08-30.
- How severe is CVE-2021-26084?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2021-26084 known to be exploited?
- Yes. CVE-2021-26084 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 215 public proof-of-concept repositories are indexed.