Covert Storage Channel Affecting @anthropic-ai/claude-code package, versions >=0.2.54 <2.1.163
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published21 Jun 2026
- disclosed17 Jun 2026
- credithackerone.com/novee
Introduced: 17 Jun 2026
NewCVE-2026-54316 (opens in a new tab)How to fix?
Upgrade @anthropic-ai/claude-code to version 2.1.163 or higher.
Overview
@anthropic-ai/claude-code is an Use Claude, Anthropic's AI assistant, right from your terminal. Claude can understand your codebase, edit files, run terminal commands, and handle entire workflows for you.
Affected versions of this package are vulnerable to Covert Storage Channel via the WebFetch tool. An attacker can access sensitive data by injecting untrusted content that triggers requests to attacker-controlled paths on a pre-approved domain, enabling covert exfiltration of files, environment variables, or command output.
Note: This is only exploitable if an attacker can add untrusted content into the context window.