Authentication Bypass Affecting rsync package, versions *


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.5% (41st percentile)

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  • Snyk IDSNYK-DEBIAN11-RSYNC-18756961
  • published13 Aug 2026
  • disclosed13 Aug 2026

Introduced: 13 Aug 2026

NewCVE-2026-53791  (opens in a new tab)
CWE-290  (opens in a new tab)

How to fix?

There is no fixed version for Debian:11 rsync.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rsync package and not the rsync package as distributed by Debian. See How to fix? for Debian:11 relevant fixed versions and status.

rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.

CVSS Base Scores

version 3.1