CVEvulnerability

CVE-2026-54316

6.0 MEDIUM Published 2026-06-23 Modified 2026-10-25 Official page ↗
Status
Analyzed
Published
2026-06-23
Last modified
2026-10-25
Assigner
[email protected]
CVSS 4.0 ([email protected])
6.0 MEDIUM — CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
9.1 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weaknesses
CWE-183, CWE-200, CWE-515

Description

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.

Affected configurations

• anthropic claude code (>= 0.2.54 < 2.1.163)

Related

Weakness · CWE (3)

  • CWE-183 Permissive List of Allowed Inputs weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor weakness
  • CWE-515 Covert Storage Channel weakness

References