CVE-2026-44470 PUBLISHED

Claude Desktop: Local Privilege Escalation via Directory Junction in CoworkVMService

Assigner: GitHub_M
Reserved: 06.05.2026 Published: 13.05.2026 Updated: 13.05.2026

The Claude Desktop app gives you Claude Code with a graphical interface built for running multiple sessions side by side. Prior to 1.3834.0, the CoworkVMService component in Claude Desktop for Windows ran as SYSTEM and did not validate whether the VM bundle directory was a real directory or an NTFS directory junction before creating files within it. A local non-elevated user could replace the user-writable VM bundle directory with a directory junction pointing to an attacker-chosen location, causing the service to create a SYSTEM-owned file in an arbitrary directory. This could be leveraged for local privilege escalation. This vulnerability is fixed in 1.3834.0.

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.5

Product Status

Vendor anthropics
Product claude-code
Versions
  • Version < 1.3834.0 is affected

References

Problem Types

  • CWE-59: Improper Link Resolution Before File Access ('Link Following') CWE
  • CWE-269: Improper Privilege Management CWE