CVE-2026-66897

CRITICAL
INFO Priority: 0.07 BB Relevance: 70/100
Published: 2026-08-24 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction Conf. Impact Integ. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: Changed
C: High
I: High
A: High

Description

A path traversal vulnerability in LXD's instance template processing allows an attacker with container edit permissions, or any user launching a crafted image, to overwrite arbitrary files on the host system as root. When processing target template paths specified in metadata.yaml, LXD validates the path against a confined os.Root directory handle but subsequently opens and creates the file using os.Create with an unconfined string path. This discrepancy between path resolution checks and file creation allows an attacker to escape directory confinement, overwrite root-owned host files, and achieve host root code execution.

Weakness Classification (2)

Affected Software (4)

VendorProductVersion
canonical lxd < 4.0.13
canonical lxd 5.0.0 – 5.0.9
canonical lxd 5.1 – 5.21.7
canonical lxd 6.0 – 6.9

References & Advisories (1)

Bug Bounty Relevance

70 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

9.9 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS — Exploitation Probability

0.72%
Raw Score 0.007170
Percentile 53.7%
Date 2026-10-28

Intelligence Sources

nvd ref →