CVE-2026-53791

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 v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0	Product Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header	Release Notes Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-13 15:19

Updated : 2026-08-31 15:38

NVD link : CVE-2026-53791

Mitre link : CVE-2026-53791

CVE.ORG link : CVE-2026-53791

JSON object : View

Products Affected

samba

rsync

CWE

CWE-290

Authentication Bypass by Spoofing

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