CVE-2026-63343 PUBLISHED

Arbitrary File Read/Write: metadata.yaml symlink in image allows host filesystem access as root

Assigner: GitHub_M
Reserved: 16.07.2026 Published: 21.08.2026 Updated: 21.08.2026

Incus is a system container and virtual machine manager. Prior to version 7.3.0, a malicious image containing a metadata.yaml symlink pointing to an arbitrary host path allows an authenticated Incus user to read or overwrite any file on the host as root via the instance metadata API. The exec-output and templates/ paths were patched in a prior release using Lstat rejection and os.OpenRoot confinement; metadata.yaml was not included in either patch and remains exploitable. Version 7.3.0 patches the issue.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS Score: 9.9

Product Status

Vendor lxc
Product incus
Versions
  • Version < 7.3.0 is affected

References

Problem Types

  • CWE-73: External Control of File Name or Path CWE