CVE-2026-70453

rsync before 3.5.0 contains an algorithmic complexity vulnerability in the hash_search() function that allows a remote attacker to cause a denial of service by delivering a carefully constructed file list. A sender can exploit the quadratic-time worst-case behavior in hash lookups to exhaust receiver CPU resources with a modest number of crafted entries, causing a sustained denial of service.

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
https://github.com/RsyncProject/rsync/security/advisories/GHSA-8x5r-mjx8-83hv
https://www.vulncheck.com/advisories/rsync-algorithmic-complexity-dos-via-hash-search

Configurations

No configuration.

History

23 Oct 2026, 18:10

Type	Values Removed	Values Added
Summary		(es) rsync anterior a 3.5.0 contiene una vulnerabilidad de complejidad algorítmica en la función hash_search() que permite a un atacante remoto causar una denegación de servicio al entregar una lista de archivos cuidadosamente construida. Un remitente puede explotar el comportamiento de peor caso de tiempo cuadrático en las búsquedas de hash para agotar los recursos de CPU del receptor con un número modesto de entradas manipuladas, causando una denegación de servicio sostenida.

Information

Published : 2026-08-13 15:19

Updated : 2026-10-24 16:10

NVD link : CVE-2026-70453

Mitre link : CVE-2026-70453

CVE.ORG link : CVE-2026-70453

JSON object : View

Products Affected

No product.

CWE

CWE-407

Inefficient Algorithmic Complexity

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