Black October

Railway Breach Exposes Up to 100,000 Workspaces After Attackers Steal AI Credentials for $740,000 in Fraudulent Usage

Railway disclosed that attackers exploited two previously unknown vulnerabilities in its build infrastructure starting October 20 to escape filesystem isolation and access internal credentials. The threat actors retrieved Railway's source code, analyzed it to find additional weaknesses, and then abused an improperly configured trust relationship to decrypt and steal customer environment variables. The incident affected a maximum of 1.85 percent of workspaces, or roughly 100,000, though the exact number of stolen secrets remains unconfirmed. Stolen credentials were used to generate approximately $740,000 in unauthorized AI usage, with Railway committing to cover any unreimbursed charges from providers. The company also reset GitHub OAuth tokens and AI agent keys belonging to 1,852 users. Railway linked the campaign to the broader "Black October" wave of attacks against AI platforms including Northflank, OpenCode, Warp, and Lightning AI, and stated that all attackers were removed by October 21 with vulnerabilities now remediated.