CVE-2026-70455

rsync 3.4.2 before 3.5.0 contains a denial of service vulnerability that allows a remote sender to exhaust system resources by specifying the --zt short alias for --compress-threads, which bypasses the refuse options directive's string matching on long option names. Attackers can specify --zt=N with a large value to spawn an unbounded number of Zstandard worker threads on the receiver, exhausting available thread and memory resources.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0	Product Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-rjvj-qgqg-cvx9	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-dos-via-zt-zstandard-compression-thread-exhaustion	Release Notes Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

23 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) rsync 3.4.2 anterior a 3.5.0 contiene una vulnerabilidad de denegación de servicio que permite a un remitente remoto agotar los recursos del sistema al especificar el alias corto --zt para --compress-threads, lo que elude la coincidencia de cadenas de la directiva refuse options en nombres de opciones largos. Los atacantes pueden especificar --zt=N con un valor grande para generar un número ilimitado de hilos de trabajo Zstandard en el receptor, agotando los recursos de hilos y memoria disponibles.

Information

Published : 2026-08-13 15:19

Updated : 2026-10-24 16:10

NVD link : CVE-2026-70455

Mitre link : CVE-2026-70455

CVE.ORG link : CVE-2026-70455

JSON object : View

Products Affected

samba

rsync

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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