CVE-2026-70637

LightFTP through 2.4 contains multiple data race vulnerabilities in ftpserv.c that allow anonymous attackers to cause undefined behavior by issuing LIST followed by ABOR commands without authentication. The control thread closes data_socket and file_fd descriptors while worker threads concurrently operate on the same fields in worker_thread_cleanup, allowing stale file descriptors to be reassigned by the OS and subsequently used by worker threads on unrelated resources, resulting in potential denial of service.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/hfiref0x/LightFTP/issues/75
https://www.vulncheck.com/advisories/lightftp-data-race-condition-via-abor-command-in-ftpserv-c

Configurations

No configuration.

History

23 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) LightFTP hasta la versión 2.4 contiene múltiples vulnerabilidades de condición de carrera de datos en ftpserv.c que permiten a atacantes anónimos causar un comportamiento indefinido al emitir comandos LIST seguidos de ABOR sin autenticación. El hilo de control cierra los descriptores data_socket y file_fd mientras los hilos de trabajo operan concurrentemente en los mismos campos en worker_thread_cleanup, permitiendo que descriptores de archivo obsoletos sean reasignados por el SO y posteriormente utilizados por los hilos de trabajo en recursos no relacionados, lo que resulta en una potencial denegación de servicio.

Information

Published : 2026-08-06 15:17

Updated : 2026-10-24 15:10

NVD link : CVE-2026-70637

Mitre link : CVE-2026-70637

CVE.ORG link : CVE-2026-70637

JSON object : View

Products Affected

No product.

CWE

CWE-820

Missing Synchronization

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