CVE-2026-87799

Estado: AplazadaCrítica (9.9)—

Improper link resolution in the migration receive path in Canonical LXD versions 4.0 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client that can create instances or custom storage volumes in a project, or a malicious migration source server, to write attacker-controlled files to arbitrary paths on the target host as root, leading to full host compromise. The attacker does this with a crafted rsync or btrfs send stream that plants a symlink in the transferred volume, such as rootfs or root.img, and then writes through it.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.41%
Percentil entre todas las CVEs puntuadas: 33
Fecha de la puntuación: 4/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement85 %
Impacto principalT1068 Exploitation for Privilege Escalationprivilege escalation90 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact85 %

AV:N, PR:L requiere acceso autenticado a servicio remoto LXD; symlink en rsync/btrfs permite escritura de archivos como root en rutas arbitrarias, escalada y manipulación del host.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Threat Intelligence Program Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning Restrict File and Directory Permissions

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Canonical — LXD^AI

CWE

CWE-59

Referencias

https://github.com/canonical/lxd/security/advisories/GHSA-fmc3-3cpq-6whr

JSON original (NVD)

Mostrar

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          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "none"
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            {
              "automatable": "no"
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            {
              "technicalImpact": "total"
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          "version": "2.0.3",
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    {
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      "value": "Improper link resolution in the migration receive path in Canonical LXD versions 4.0 and later (fixed in 4.0.14, 5.0.10, 5.21.8 and 6.10) on Linux allows an authenticated client that can create instances or custom storage volumes in a project, or a malicious migration source server, to write attacker-controlled files to arbitrary paths on the target host as root, leading to full host compromise. The attacker does this with a crafted rsync or btrfs send stream that plants a symlink in the transferred volume, such as rootfs or root.img, and then writes through it."
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  "lastModified": "2026-09-29T04:18:01.037",
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