2026-11-10
mittwald MCP Server Flaw Exploited, 56 Customer Projects Compromised (November 2026): The Published Timeline and What Users and AI-Integration Operators Should Do
German web hosting company mittwald said in an official blog post that a flaw in its MCP server, which connects customers' AI assistants to its control panel mStudio, was exploited and 56 customer projects were compromised. According to the company, the attacker first tested the flaw on October 21, began acting as a regular user with test accounts from October 23, and exploited the flaw at 15:03 on October 27 using another account. The company treats all data from October 27 onward as compromised. Unusual behaviour was found on November 4, and the same day the company identified the MCP server as the entry point and shut it down. On November 6 it forensically examined the 56 compromised projects and the MCP server, found no further compromised projects, and says it cannot currently detect any attacker activity. No passwords were read out; what was read out were users' session tokens, all of which have been revoked, it says. The customer centre and the websites managed there were not affected. The MCP server remains offline, and whether it returns will be decided after the investigation. The company says the attacker's speed suggests the use of AI tools; this is the company's suspicion. It says it will publish a detailed account the following week. Our view: for MCP servers that connect AI assistants to hosting or production environments, the key points are narrowly scoped, short-lived tokens and monitoring that can catch the probing stage.