UPDATE: On June 3, 2022, Atlassian updated its security advisory with new information regarding a fix for Confluence Server and Data Center to address CVE-2022-26134. Users are encouraged to update immediately to mitigate their risk. Additional observations after publication of this blog post have been shared here, with guidance on how to verify if you have been impacted by unauthorized access.  Over the Memorial Day weekend in the United States, Volexity conducted an incident response investigation involving two Internet-facing web servers belonging to one of its customers that were running Atlassian Confluence Server software. The investigation began after suspicious activity was detected on the hosts, which included JSP webshells being written to disk. Volexity immediately used Volexity Surge Collect Pro to collect system memory and key files from the Confluence Server systems for analysis. After a thorough review of the collected data, Volexity was able to determine the server compromise stemmed from … Continue reading Zero-Day Exploitation of Atlassian Confluence