Researchers warn that OpenCode quietly fixed a critical RCE vulnerability, leaving users at risk
Researchers Warn OpenCode Quietly Patched Critical RCE Flaw, Leaving Users At Risk
Pillar Security disclosed a critical remote code execution (RCE) vulnerability in the open-source AI coding tool OpenCode, affecting versions 1.0.137 to 1.18.32. The vendor fixed it in 1.18.33 but did not publish a CVE or security advisory, and researchers warn that conventional vulnerability scanners and dependency alerts cannot identify affected installations. The vulnerability affects Windows and WSL; an attacker-controlled MCP server can execute arbitrary code on the developer's machine during MCP OAuth authentication without additional user interaction. Pillar Security reported it privately through a GitHub Security Advisory in late August 2026; OpenCode's parent company Anomaly confirmed receiving the report but said a malicious MCP server is outside its threat model, and the fix was completed on September 28.
When OpenCode fixed this critical vulnerability, it did not publish a CVE or security advisory, making affected versions difficult for conventional scanners and dependency alerts to identify.