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CVE-2026-66898 (GCVE-0-2026-66898)

Vulnerability from cvelistv5 – Published: 2026-08-12 20:07 – Updated: 2026-08-13 13:40
VLAI
Title
Path traversal via unvalidated instance name in backup tarball restore enables root file write / RCE
Summary
A path traversal vulnerability in LXD allows an attacker to manipulate file system paths during backup import and restore operations. When importing or restoring a backup archive, LXD fails to validate instance and storage volume names contained within the archive metadata. An attacker can exploit this flaw by supplying a crafted backup archive with malicious instance or volume names containing path traversal sequences, potentially allowing file access or overwriting outside the designated restore directory.
Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 13:40 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
URL Tags
https://github.com/canonical/lxd/security/advisor… vdb-entryvendor-advisory
Impacted products
Vendor Product Version CPE status
Canonical LXD Affected: 4.0.0 , < 4.0.12 (semver)
Affected: 5.0.0 , < 5.0.4 (semver)
Affected: 5.21.0 , < 5.21.2 (semver)
Affected: 6.0 , < 6.1 (semver)
guessed Create a notification for this product.
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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