CVE-2026-81849
Improper limitation of a pathname to a restricted directory in the aws:downloadContent plugin in amazon-ssm-agent before 3.3.4515.0 might allow an authenticated remote user whose ssm:SendCommand permission is restricted to the AWS-DownloadContent document, to write arbitrary files outside the intended download directory with root privileges, via crafted object keys in the S3 source the document is directed to retrieve. This issue may lead to arbitrary code execution as root if specific sensitive files are overwritten.
To remediate this issue, customers should upgrade amazon-ssm-agent to version 3.3.4515.0 or later.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 8.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.90%
- Percentil entre todas las CVEs puntuadas: 58
- Fecha de la puntuación: 6/10/2026
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.
- Explotación
T1210Exploitation of Remote Serviceslateral movement85 % - Impacto principal
T1005Data from Local Systemcollection75 % - Impacto secundario
T1059Command and Scripting Interpreterexecution80 % - Impacto secundario
T1565.001Stored Data Manipulationimpact70 %
Vulnerabilidad path traversal (CWE-23) en servicio remoto AWS SSM que requiere autenticación (PR:L) y permite escritura arbitraria de archivos con privilegios root, causando ejecución de código remota.
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
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-23
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-81849",
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"metrics": {
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"timestamp": "2026-08-31T18:44:40.602919Z"
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"published": "2026-08-28T20:20:13.940",
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"description": [
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"descriptions": [
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"value": "Improper limitation of a pathname to a restricted directory in the aws:downloadContent plugin in amazon-ssm-agent before 3.3.4515.0 might allow an authenticated remote user whose ssm:SendCommand permission is restricted to the AWS-DownloadContent document, to write arbitrary files outside the intended download directory with root privileges, via crafted object keys in the S3 source the document is directed to retrieve. This issue may lead to arbitrary code execution as root if specific sensitive files are overwritten.\n\n\n\nTo remediate this issue, customers should upgrade amazon-ssm-agent to version 3.3.4515.0 or later."
}
],
"lastModified": "2026-08-31T19:17:15.310",
"sourceIdentifier": "ff89ba41-3aa1-4d27-914a-91399e9639e5"
}