CVE-2026-54316

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.

Score

CVSS 3.1 9.1 Critical

Status

Analyzed - security-advisories@github.com

Published

2026-06-23

Last modified

2026-10-25

Weaknesses

CWE-183, CWE-200, CWE-515

Affected products

• Claude Code (Anthropic)
• Claude-code (Anthropics)

References

• https://github.com/anthropics/claude-code/security/advisories/GHSA-fg94-h982-f3mm