INSECURE CREDENTIAL STORAGE PLAGUES MCP

Summary from the TLDR InfoSec newsletter

Many MCP environments rely upon long-lived credentials such as API keys, but they store them incorrectly in world-readable files or get leaked via chat logs. The community-provided MCP server for Figma even stores its credentials in a world-readable and world-writeable file that attackers can use for session fixation attacks. OAuth should be implemented in MCP servers for apps that support it, and other MCP servers should consider using OS native credentials stores such as macOS Keychain and Windows' Credentials Storage API.