CVE-2026-46406

medium

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.

References

https://github.com/anthropics/claude-code/security/advisories/GHSA-4vp2-6q8c-pvq2

Details

Source: Mitre, NVD

Published: 2026-06-29

Updated: 2026-06-29

Risk Information

CVSS v2

Base Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 7.1

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Severity: High

CVSS v4

Base Score: 4.4

Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N

Severity: Medium