CVE-2025-65099: Anthropic Claude Code

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

Claude Code is an agentic coding tool. Prior to version 1.0.39, when running on a machine with Yarn 3.0 or above, Claude Code could have been tricked to execute code contained in a project via yarn plugins before the user accepted the startup trust dialog. Exploiting this would have required a user to start Claude Code in an untrusted directory and to be using Yarn 3.0 or above. This issue has been patched in version 1.0.39.

Affected products

• Anthropic Claude Code: before 1.0.39 (fixed in 1.0.39)

Published 2025-11-19. Last modified 2026-06-17.