CVE-2026-53786

rsync before 3.5.0 contains a filter rule bypass vulnerability that allows authenticated clients to override module-level filter restrictions by supplying malicious --filter merge file directives. Attackers can inject client-side merge file directives during filter evaluation to introduce rules that supersede daemon module-level restrictions, gaining access to files the module filter was intended to exclude.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

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-mrc3-6cwx-hch6	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-filter-rule-bypass-via-filter-merge-directive	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 15:39

NVD link : CVE-2026-53786

Mitre link : CVE-2026-53786

CVE.ORG link : CVE-2026-53786

JSON object : View

Products Affected

samba

rsync

CWE

CWE-863

Incorrect Authorization

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