CVE-2026-70464

rsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake Stall

Published Aug 13, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
rsync daemon 2.0.0 before 3.5.0 contains a denial of service vulnerability that allows unauthenticated remote attackers to exhaust daemon connection slots by stalling the handshake process before or after module selection without triggering the I/O timeout. Attackers can open many simultaneous connections and trickle data at the minimum rate to avoid timeout, or stall entirely before module selection where no timeout applies, consuming all available connection slots and denying service to legitimate clients.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4888-1 rsync security update
Debian DSA Debian DSA DSA-6527-1 rsync security update
History
Type Values Removed Values Added
First Time appeared Samba
Samba rsync
CPEs cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*
Vendors & Products Samba
Samba rsync
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Rsync Project
Rsync Project rsync
Vendors & Products Rsync Project
Rsync Project rsync
Type Values Removed Values Added
Description rsync daemon 2.0.0 before 3.5.0 contains a denial of service vulnerability that allows unauthenticated remote attackers to exhaust daemon connection slots by stalling the handshake process before or after module selection without triggering the I/O timeout. Attackers can open many simultaneous connections and trickle data at the minimum rate to avoid timeout, or stall entirely before module selection where no timeout applies, consuming all available connection slots and denying service to legitimate clients.
Title rsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake Stall
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Aug 14, 2026, 4:51 PM
Reserved
Aug 4, 2026, 2:52 PM
Status
Analyzed
Published
Aug 13, 2026, 3:20 PM
Modified
Nov 3, 2026, 9:39 PM