8.7
HIGH CVSS 4.0
CVE-2026-70464
rsync 2.0.0 < 3.5.0 Connection Slot Exhaustion DoS via Handshake Stall
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.

INFO

Published Date :

Aug. 13, 2026, 3:20 p.m.

Last Modified :

Aug. 13, 2026, 3:20 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-70464 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update rsync to a version that mitigates the denial of service vulnerability in connection handling.
  • Update rsync to version 3.5.0 or later.
  • Configure connection limits and timeouts.
  • Monitor network traffic for suspicious patterns.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-70464.

URL Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
https://github.com/RsyncProject/rsync/security/advisories/GHSA-hrwq-ccf7-rw5m
https://www.vulncheck.com/advisories/rsync-connection-slot-exhaustion-dos-via-handshake-stall
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-70464 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-70464 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-70464 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 13, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://github.com/RsyncProject/rsync', 'vendor': 'RsyncProject', 'product': 'rsync', 'versions': [{'status': 'affected', 'version': '2.0.0', 'versionType': 'semver', 'lessThanOrEqual': '3.4.4'}, {'status': 'unaffected', 'version': '3.5.0', 'versionType': 'semver'}], 'packageURL': 'pkg:github/RsyncProject/rsync', 'defaultStatus': 'unaffected'}]
    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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Reference https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
    Added Reference https://github.com/RsyncProject/rsync/security/advisories/GHSA-hrwq-ccf7-rw5m
    Added Reference https://www.vulncheck.com/advisories/rsync-connection-slot-exhaustion-dos-via-handshake-stall
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.