---
id: CVE-2026-70464
title: "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 trigger…"
summary: "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 trigger…"
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-770
published: '2026-08-13'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T20:28:37.587'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70464'
references:
  - url: 'https://github.com/RsyncProject/rsync/releases/tag/v3.5.0'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/RsyncProject/rsync/security/advisories/GHSA-hrwq-ccf7-rw5m
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/rsync-connection-slot-exhaustion-dos-via-handshake-stall
    label: disclosure@vulncheck.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-70464.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-70464'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2515380'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-70464'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-70464'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67463'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67462'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00573
epssPercentile: 0.45824
ingestedAt: '2026-09-08T21:11:12.277Z'
vendor: Red Hat
product: Red Hat Enterprise Linux BaseOS (v. 10)
affected:
  - enterprise_linux 6
  - enterprise_linux 7
  - enterprise_linux 8
  - openshift_container_platform 4
  - enterprise_linux_appstream_v_10
  - enterprise_linux_appstream_v_9
  - enterprise_linux_baseos_v_10
  - enterprise_linux_baseos_v_9
patched:
  - enterprise_linux_appstream_v_10
  - enterprise_linux_appstream_v_9
  - enterprise_linux_baseos_v_10
  - enterprise_linux_baseos_v_9
---

## Overview

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

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:67463** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67463)
- **RHSA-2026:67462** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67462)
- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat OpenShift Container Platform 4 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-70464.json)