CVE-2026-46406
Claude Code: Insecure Temporary File in /copy Command Enables Response Disclosure and Symlink-Based File Write
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | Medium4.4 | 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 |
| NVDNVD · Analyzed | 4.0 | Medium4.4 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.15% · top 95% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.4.
Weakness
- CWE-59: Improper Link Resolution Before File Access ('Link Following') (opens in a new tab)All about CWE-59 and its CVEs
- CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (opens in a new tab)All about CWE-200 and its CVEs
- CWE-377: Insecure Temporary File (opens in a new tab)All about CWE-377 and its CVEs
Affected products
- affected >= 2.1.59, < 2.1.128
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@anthropic-ai/claude-codeGHSA-4vp2-6q8c-pvq2 (opens in a new tab)
References (1)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-4vp2-6q8c-pvq2 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-46406)Record last updated .