Resource exhaustion in Rsync - CVE-2026-70464
Published: August 13, 2026
Vulnerability identifier: #VU142278
CSH Severity: Medium
CVSS v4: 8.7 [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]
CVE-ID: CVE-2026-70464
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to uncontrolled resource consumption in the rsync daemon handshake handling when processing pre-transfer handshake input. A remote attacker can stall the connection by sending an unterminated line or trickling NUL-terminated arguments one byte at a time to cause a denial of service.
A stall after module selection can hold a max-connections slot and make the module unavailable to legitimate clients.
Affected software
Rsync
How to mitigate CVE-2026-70464
Install security update from vendor's website.
Rsync - update to 3.5.0