CVE-2026-53791

rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header

Published: Aug 13, 2026Updated: Aug 31, 2026 Sources: CVE List NVDCWE-290

9.1CRITICAL

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-290

Affected Products

samba

oss-project·DE

rsyncOn-prem

OSS Libraries / generic-library

RsyncProject

oss-projectaka rsync project, rsync

rsyncLibrary

OSS Libraries / generic-library

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/RsyncProject/rsync/releases/tag/v3.5.0

github.com

https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635

github.com

https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header

vulncheck.com

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