CVE-2026-43617

Updated on 20 May 2026

Severity

4.8 Medium severity

Details

CVSS score
4.8
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Overview

About vulnerability

Rsync version 3.4.2 and prior contain an authorization bypass vulnerability in the rsync daemon’s hostname-based access control list enforcement when configured with chroot. Attackers can bypass hostname-based deny rules by controlling the PTR record for their source IP address, allowing connections from hostnames that administrators intended to deny when reverse DNS resolution fails and defaults to UNKNOWN.

Details

Affected packages:
rsync @ 3.1.3 (+16 more)
Rsync version 3.4.2 and prior contain an authorization bypass vulnerability in the rsync daemon’s hostname-based access control list enforcement when configured with chroot. Attackers can bypass hostname-based deny rules by controlling the PTR record for their source IP address, allowing connections from hostnames that administrators intended to deny when reverse DNS resolution fails and defaults to UNKNOWN.

Fixes