CVE-2026-54316

MEDIUM
MEDIUM Priority: 0.03 BB Relevance: 62/100
Published: 2026-06-23 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Conf. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: Present
VC: High
VI: None
VA: None

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.

Weakness Classification (3)

Affected Software (1)

VendorProductVersion
anthropic claude_code 0.2.54 – 2.1.163

Bug Bounty Relevance

62 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

6.0 / 10.0 v4.0
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

EPSS — Exploitation Probability

0.52%
Raw Score 0.005200
Percentile 44.1%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00520
2026-10-28
0.00520

Intelligence Sources

nvd ref →