CVE-2026-70457

Estado: AnalizadaAlta (8.3)—

rsync 3.2.3 before 3.5.0 contains an out-of-bounds write in parse_size_arg() where the return value of snprintf() is used directly as an index into a .bss-segment array without bounds checking. When snprintf truncates the formatted size string, the return value equals the number of characters that would have been written including the truncated portion, and this value may exceed the array length. The subsequent indexed write targets memory outside the intended array bounds, corrupting .bss memory.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/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: 8.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.38%
Percentil entre todas las CVEs puntuadas: 29
Fecha de la puntuación: 5/10/2026

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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto principalT1059 Command and Scripting Interpreterexecution70 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact65 %

Acceso remoto sin privilegios (AV:N, PR:N) a rsync. Out-of-bounds write en memoria .bss permite corrupción de datos y potencial ejecución de código. Confianza moderada por requerir condiciones específicas (AC:H).

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

Privileged Account Management Vulnerability Scanning Restrict Web-Based Content Restrict File and Directory Permissions Remote Data Storage Network Segmentation

Tecnologías afectadas (1)

Samba — Rsync

CWE

CWE-131, CWE-787

Referencias

JSON original (NVD)

Mostrar

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