Hackers hit AI coding tool OpenCode, running up charges on users’ AI accounts

The weekend episode drew a response from David Sacks, co-chair of the President’s Council of Advisors on Science and Technology.

“OpenCode (and earlier Hugging Face) hit the same wall mid-attack: frontier models refused to analyze the very exploits needed for defense because the payloads tripped safety filters. The guardrails backfired,” he wrote on X.

The breach occurred the same night OpenCode made GLM-5.3-Flash free for users. The broader GLM-5.3 family has drawn attention from researchers who study open-weight models and note that its cybersecurity capabilities approached levels previously associated with restricted-access models like Anthropic’s Claude Mythos Preview. 

OpenCode has not detailed how attackers gained access to the older system, how keys were stored, or the full extent of any misuse. It has told affected users to revoke and replace their keys directly with each provider. The company said the incident remains ongoing.

The breach lands amid a run of AI-enabled cyber incidents. Earlier this month, cybersecurity firm CrowdStrike said a China-based hacker likely used an AI penetration-testing agent, which probes computer systems for weaknesses, and Claude in attacks on South Korean banks. Last week, India’s cybersecurity agency warned that AI agents, including some being tested by AI companies, had reached Indian organizations’ systems without authorization.