Vulnerability · Published Aug 13, 2026 · Assigned by VulnCheck
CVE-2026-70464rsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake Stall
High 7.5
In plain English
A high-severity resource allocation without limits in rsync from RsyncProject. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | rsync | 3.5.0-3.el10_2 | ALSA-2026:67463 |
| AlmaLinux:8 | rsync | 3.1.3-28.el8_10 | ALSA-2026:74095 |
| AlmaLinux:9 | rsync | 3.2.7-1.el9_8 | ALSA-2026:67462 |
| AlmaLinux:10 | rsync-daemon | 3.5.0-3.el10_2 | ALSA-2026:67463 |
| AlmaLinux:8 | rsync-daemon | 3.1.3-28.el8_10 | ALSA-2026:74095 |
| AlmaLinux:9 | rsync-daemon | 3.2.7-1.el9_8 | ALSA-2026:67462 |
| AlmaLinux:10 | rsync-rrsync | 3.5.0-3.el10_2 | ALSA-2026:67463 |
| AlmaLinux:9 | rsync-rrsync | 3.2.7-1.el9_8 | ALSA-2026:67462 |
| Alpine:v3.21 | rsync | 3.5.0-r0 | ALPINE-CVE-2026-70464 |
| Alpine:v3.22 | rsync | 3.5.0-r0 | ALPINE-CVE-2026-70464 |
| Alpine:v3.23 | rsync | 3.5.0-r0 | ALPINE-CVE-2026-70464 |
| Alpine:v3.24 | rsync | 3.5.0-r0 | ALPINE-CVE-2026-70464 |
| Debian:12 | rsync | no fix listed | DEBIAN-CVE-2026-70464 |
| Debian:13 | rsync | 3.5.0+ds1-0+deb13u1 | DEBIAN-CVE-2026-70464 |
| Debian:14 | rsync | 3.5.0+ds1-1 | DEBIAN-CVE-2026-70464 |
| Rocky Linux:10 | rsync | 0:3.5.0-3.el10_2 | RLSA-2026:67463 |
| Rocky Linux:8 | rsync | 0:3.1.3-28.el8_10 | RLSA-2026:74095 |
| Rocky Linux:9 | rsync | 0:3.2.7-1.el9_8 | RLSA-2026:67462 |
| Ubuntu:22.04:LTS | rsync | no fix listed | UBUNTU-CVE-2026-70464 |
| Ubuntu:24.04:LTS | rsync | no fix listed | UBUNTU-CVE-2026-70464 |
| Ubuntu:26.04:LTS | rsync | no fix listed | UBUNTU-CVE-2026-70464 |
| Ubuntu:26.10 | rsync | no fix listed | UBUNTU-CVE-2026-70464 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| RsyncProject | rsync | 2.0.0 – through 3.4.4 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- GitHub Security Advisory (GHSA-hrwq-ccf7-rw5m) vendor-advisory
- rsync 3.5.0 Release Notes release-notes
- https://www.vulncheck.com/advisories/rsync-connection-slot-exhaustion-dos-via-handshake-stall third-party-advisory