CVE-2026-35021 Details

A command injection vulnerability has been identified in Anthropic's Claude Code CLI and Claude Agent SDK. This vulnerability allows attackers to execute arbitrary commands by injecting shell metacharacters into file paths, which are then executed as shell commands. The issue arises in the prompt editor invocation utility, where the file path is improperly sanitized before being interpolated into a command executed via execSync. Although the path is enclosed in double quotes, POSIX shell rules permit command substitution within quotes, enabling the execution of injected commands with the privileges of the user running the CLI.

Users are advised to set the ANTHROPIC_API_KEY environment variable directly, bypassing the CLI's authentication helper execution. In CI/CD environments, it is recommended to generate Claude CLI settings from trusted sources and to avoid using the -p mode with untrusted workspaces.