Attackers Crash Claude's 'Office Party' Flaw to Run Malicious Code on Linux

An attacker can use a flaw in Anthropic Claude's document-processing tool to run malicious code on Linux systems just by creating a temporary file that the AI assistant can access. The flaw highlights a growing risk posed by even trusted AI tools to introduce security gaps in enterprise environments. Researchers from AIR Security discovered the flaw, which they've dubbed "Office Party," in Anthropic's official DOCX, PPTX, and XLSX skills, which are tools that enable Claude to create, read, edit, and process Microsoft Word documents, PowerPoint presentations, and Excel spreadsheets, respectively. The vulnerability stems from a helper script, soffice.py, that launches LibreOffice to convert documents, including rendering Word documents as PDFs, they revealed in a report published today. When the script encounters an environment where Unix-domain sockets cannot be opened, it uses a workaround that loads a shared library through the Linux LD_PRELOAD mechanism. Anthropic has opted not to fix the issue. During conversation, the script checks whether a library named lo_socket_shim.so already exists in a shared temporary directory but does not verify its origin or contents. An attacker who can place a malicious library at that location before the next document-processing operation can potentially have their code loaded and executed within LibreOffice, with the privileges of the user running the AI agent. In this way, the flaw can allow attackers to execute malicious code on a user's ...