CVE-2026-53791: rsync before 3.5.0 (exclusive), 0 through 3.4.4

CVE-2026-53791. CVSS 3.1 base score 9.1 (CRITICAL, Vendor/CNA). EPSS 0.00501 (percentile 0.41991), scored 22-Oct-2026.

Affected technology

rsync · before 3.5.0 (exclusive)
samba

rsync · 0 through 3.4.4
RsyncProject

Description’s affected range: before 3.5.0

Component: Not specified by the source

Attack conditions (Vendor/CNA, CVSS 4.0): Network (remote) · No privileges required · No user interaction required

What an attacker can do

Unauthenticated remote attackers can bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Vendor/CNA’s CVSS 4.0 assessment (base score 9.1/10) rates confidentiality and integrity impact as high; availability impact as none.

Published 24-Oct-2026 01:43 UTC

CWE: CWE-290
CCR priority: 36.5 /100 (P4)
CVSS 3.1: 9.1 /10 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N · Vendor/CNA
EPSS: 0.00501 · percentile 0.41991 · 2026-10-22
KEV: no

Provenance

NVD CVE API 2.0 · Source record · observed 2026-10-24 01:40:49.068977+00:00 UTC

Stable permalink: https://cybercodered.org/item/cve-cve-2026-53791.html