CVE-2026-46406

MEDIUM CVSS 4.0: 4.4 EPSS 0.12%
Updated Jun 30, 2026
Anthropic
Parameter Value
CVSS 4.4 (MEDIUM)
Affected Versions 2.1.58 — 2.1.128
Fixed In 2.1.128
Type CWE-200 (Information Exposure), CWE-377, CWE-59 (Improper Link Resolution)
Vendor Anthropic
Public PoC No

Claude Code is an agentic coding tool. From 2.1.59 until 2.1.128, the Claude Code /copy command wrote responses to a hardcoded, predictable path (/tmp/claude/response.md) without UID isolation, randomness, or symlink protection. The file was created world-readable (0644) in a world-traversable directory (0755), allowing any local user to read a privileged user's Claude response, which could contain secrets or credentials.

Additionally, because the path was static and predictable, a local attacker could pre-create the directory and plant a symlink at the expected file path, causing the privileged process to follow the symlink and overwrite an attacker-chosen file with the response text. Exploiting this required a local unprivileged user on the same system and a privileged user to run the /copy command. This vulnerability is fixed in 2.1.128.

Attack Parameters

Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
Low
Basic privileges needed
User Interaction
Active
User action required

Impact Assessment

Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Anthropic Claude_Code
cpe:2.3:a:anthropic:claude_code:*:*:*:*:*:node.js:*:*
2.1.58 2.1.128