CVE-2026-85526

Status: DeferredCritical (9.9)—

Path traversal in the Btrfs storage driver (unpackVolume) in Canonical LXD on Linux allows an authenticated user with instance creation privileges to delete or replace arbitrary files and directories on the host filesystem as root via a crafted subvolumes[].path entry in backup/optimized_header.yaml during a btrfs optimized backup import.

CVSS

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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.52%
Percentile among all scored CVEs: 42
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1210 Exploitation of Remote Serviceslateral movement75 %
Primary impactT1565.001 Stored Data Manipulationimpact85 %
Secondary impactT1070.004 File Deletionstealth80 %

Explotación de servicio remoto (LXD) por usuario autenticado con privilegios. El path traversal en backup import permite manipular/eliminar archivos del host como root (integridad de datos).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Vulnerability Scanning Threat Intelligence Program Restrict File and Directory Permissions Privileged Account Management Remote Data Storage Network Segmentation

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Canonical — LXD^AI

CWEs

CWE-22

References

Raw JSON (NVD)

Show

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