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CVE-2026-63091

Estado: AnalizadaAlta (7.1)—

ProFTPD before 1.3.9c and 1.3.10rc3 contains a signed integer overflow vulnerability in the mod_sftp module's SCP size-record parser that allows authenticated low-privilege attackers to bypass ASLR by sending a crafted file size value of UINT64_MAX, which results in a negative off_t value. Attackers can exploit the subsequent conversion to uint32_t, causing an approximately 4 GB requested read length and forcing the server to read beyond the end of the SSH channel data and write overread process memory into the uploaded file.

Leer descripción completaMostrar menos

In tested configurations, the disclosed data contains libc, libcrypto, and PIE pointers sufficient to derive their randomized base addresses, thereby bypassing ASLR and enabling reliable exploitation of memory corruption vulnerabilities in the same process.

CVSS

Probabilidad de explotación (EPSS)

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.

Vulnerabilidad de overflow en mod_sftp (servicio remoto SSH/SCP) que requiere autenticación (PR:L). El atacante lee memoria del proceso (libc, libcrypto, PIE) para derivar direcciones ASLR, revelando credenciales y pointers (T1005, T1552). Habilita explotación posterior de corrupción de memoria (T10

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

Update SoftwareThreat Intelligence ProgramPrivileged Account ManagementApplication Isolation and SandboxingExploit ProtectionActive Directory Configuration

Tecnologías afectadas (1)

Proftpd — Proftpd

CWE

Referencias

JSON original (NVD)

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