CVE-2025-55284highData leakage2025-08-18
CVE-2025-55284: Claude Code's Permissive Default Allowlist Enables Unauthorized File Read and Network Exfiltration in Claude Code
Due to an overly broad allowlist of safe commands, it was possible to bypass the Claude Code confirmation prompts to read a file and then send file contents over the network without user confirmation.
What it is
Due to an overly broad allowlist of safe commands, it was possible to bypass the Claude Code confirmation prompts to read a file and then send file contents over the network without user confirmation. Reliably exploiting this requires the ability to add untrusted content into a Claude Code context window.
Users on standard Claude Code auto-update received this fix automatically after release. Current users of Claude Code are unaffected, as versions prior to 1.0.24 are deprecated and have been forced to update.
How to check
- Affected: @anthropic-ai/claude-code (npm) < 1.0.4.
- Compare your installed version with the range above (command below).
How to fix
- Upgrade @anthropic-ai/claude-code to 1.0.4 or later.
npm ls @anthropic-ai/claude-code -g # or: claude --versionSources
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- criticalUpGuard: 16,326 Supabase databases had readable tables
- highCVE-2026-86063: Claude Code: Plugin Hash Pin Bypass Allows Bypass of Hash Pinning
- highCVE-2026-103435: Claude Code could be raced into writing files outside the project