CVE-2026-54316
CVE-2026-54316 · Claude Code: Out-of-Band Data Exfiltration via Pre-Approved HuggingFace Domain in WebFetch
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Claude Code is an agentic coding tool. From 0.2.54 until 2.1.163, because the hostname huggingface.co was pre-approved as a bare hostname for the WebFetch tool, any path on that domain—including attacker-controlled model repositories—was auto-approved without a permission prompt or being subject to --allowedTools restrictions. An attacker able to inject untrusted content into a Claude Code context could direct it to issue WebFetch requests against attacker-controlled repository files (e.g. /resolve/main/config.json), which HuggingFace counts as downloads server-side, creating a covert out-of-band channel for encoding and exfiltrating data Claude can access such as files, environment variables, or command output. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window. This vulnerability is fixed in 2.1.163.
CVSS 6.0 · Medium · EPSS 0.5% · Fix available
- Published
- Updated
Stack: node
Affected products and versions
claude-code
- Versions
- >= 0.2.54, < 2.1.163: Affected
No fix published
@anthropic-ai/claude-code npm
- Affected ranges
- SEMVER: ≥ 0.2.54, < 2.1.163
Update to 2.1.163