# Researchers disclose OpenCode flaw allowing commands during authentication

_Published Tuesday, October 20, 2026 at 10:09 AM EDT · Security · Latest · Tier 2 — Notable_

![Researchers disclose OpenCode flaw allowing commands during authentication — Primary](https://assets.infosecurity-magazine.com/webpage/og/ebdb7baf-8973-4446-8fdd-7293eb4e24d2.jpg)

Pillar Security disclosed an OpenCode vulnerability on October 19 that could let a malicious remote server execute code on developers' Windows or Windows Subsystem for Linux machines during authentication, Infosecurity Magazine reported. Researchers identified affected versions as 1.0.137 to 1.18.32.

The attack uses a model context protocol server, which connects external services to AI tools. An underlying dependency passed a URL to PowerShell without proper escaping, allowing embedded commands to run without additional consent.

Researchers said OpenCode patched the flaw on September 28 in version 1.18.33 without a security advisory or CVE identifier, leaving conventional scanners unable to flag affected installations. They stressed that correcting URL quoting in the dependency was essential; URL scheme checks alone were insufficient.

## Sources

- [Infosecurity Magazine](https://www.infosecurity-magazine.com/news/opencode-quietly-patched-critical/)

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Canonical: https://techandbusiness.org/newswire/aCRfR4Z-AY4Gj_7drJS5EY
Published: 2026-10-20T14:09:30.152Z
Story chronology: 2026-10-19T00:00:00.000Z
Retrieved: 2026-10-20T17:14:27.580Z
Publisher: Tech & Business (techandbusiness.org)