CVE-2026-46406 (GCVE-0-2026-46406)

Vulnerability from cvelistv5 – Published: 2026-06-29 14:03 – Updated: 2026-06-29 15:26
VLAI
Title
Claude Code: Insecure Temporary File in /copy Command Enables Response Disclosure and Symlink-Based File Write
Summary
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.
Severity
4.4 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 15:25 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-377 - Insecure Temporary File
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7831 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
anthropics claude-code Affected: >= 2.1.59, < 2.1.128
guessed Create a notification for this product.
Show details on NVD website
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