Unauthenticated OGNL Injection RCE in Atlassian Confluence Server/Data Center
CISA: Atlassian Confluence Server and Data Center Remote Code Execution Vulnerability
CVSS 3.1
9.8critical
EPSS
100%p100
Published
()
KEV added
AI analysis
Atlassian Confluence Server and Data Center contain an unauthenticated remote code execution flaw caused by improper neutralization of expression-language (OGNL) input (CWE-917): an attacker with network access to the application can submit a crafted request that is evaluated as an expression and executed by the server. Successful exploitation lets a remote, unauthenticated attacker run arbitrary code with the privileges of the Confluence process, without any credentials. All organizations running self-managed Confluence Server or Data Center are affected, particularly instances exposed to the internet; Confluence Cloud is not listed among the affected products. Exploitation is confirmed in the wild: the flaw was added to CISA's KEV on 2022-06-02 with ransomware use marked as known, and EPSS assigns a 100% probability of exploitation within 30 days (100th percentile). CVSS has not yet been scored in this data, but the KEV listing and known ransomware use make unpatched, internet-facing instances a top-priority patching target.
What to do: Immediately upgrade to the patched Confluence release specified in Atlassian's 2022-06-02 security advisory, and until patched follow the CISA required action to block all internet traffic to and from affected instances. Because in-the-wild exploitation and ransomware use are confirmed, also hunt for compromise indicators on both patched and unpatched hosts, such as webshells, unexpected child processes of the Confluence service, and unusual outbound connections.
Affected
Atlassian Confluence Server
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Atlassian Confluence Data Center
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Estimated exposure
largetens of thousands of internet-exposed instances (public scan counts of roughly 60,000-90,000 Confluence Server/Data Center hosts around the June 2022… — Basis is internet-wide public scan counts of Confluence Server/Data Center published near the time of disclosure, combined with Confluence's large self-managed enterprise installed base; the true total number of deployments, including…
Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.
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 from 1.3.0 before 7.4.17, from 7.13.0 before 7.13.7, from 7.14.0 before 7.14.3, from 7.15.0 before 7.15.2, from 7.16.0 before 7.16.4, from 7.17.0 before 7.17.4, and from 7.18.0 before 7.18.1.
CISA Known Exploited Vulnerability
Affected
Atlassian Confluence Server/Data Center
Required action
Immediately block all internet traffic to and from affected products AND apply the update per vendor instructions [https://confluence.atlassian.com/doc/confluence-security-advisory-2022-06-02-1130377146.html] OR remove the affected products by the due date on the right. Note: Once the update is successfully deployed, agencies can reassess the internet blocking rules.
Unauthenticated Confluence RCE CVE-2022-26134 was exploited in the wild; Volexity observed intrusions and Cerber ransomware on unpatched servers.
Volexity identified exploitation of CVE-2022-26134, an unauthenticated remote code execution vulnerability in Atlassian Confluence Server and Data Center, during Memorial Day weekend 2022, with Atlassian issuing a patch. Cortex Xpanse found 19,707 potentially affected Confluence instances, concentrated in the US, Germany, China, and Russia, plus 1,251 end-of-life versions exposed. Unit 42 and Cortex Managed Threat Hunting observed successful exploitation leading to reconnaissance commands and a Cerber ransomware deployment that was blocked by Cortex XDR. A public PoC has increased exploitation risk.