What’s Vulnerable › Vulnerabilities
CVE-2026-46406: Claude Code: Insecure Temporary File in /copy Command Enables Response Disclosure and Symlink-Based File Write
- Severity: medium (CVSS 6.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-29 · updated 2026-10-25
- Weakness: CWE-59
Description
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.
Affected products
- anthropics claude-code: from 2.1.58 before 2.1.128 — fixed in 2.1.128
How to fix
Upgrade to a fixed version: anthropics claude-code 2.1.128. Check the vendor advisory for mitigations.
References
Get alerted when CVE-2026-46406 or the next vulnerability affects your stack