CVE-2026-70453 HIGH

CVE-2026-70453: rsync < 3.5.0 Algorithmic Complexity DoS via hash_search()

Vendor Rsyncproject
Product rsync
Weakness CWE-407
Published August 13, 2026
Last update August 13, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

August 13, 2026 CVE published
August 13, 2026 Record updated