CVE-2026-53791

EUVD-2026-58099
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
9.1 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 51.63%
Affected Products (NVD)
VendorProductVersion
sambarsync
𝑥
< 3.5.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
rsync
bookworm
vulnerable
bookworm (security)
vulnerable
forky
3.5.0+ds1-3
fixed
sid
3.5.0+ds1-3
fixed
trixie
vulnerable
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
rsync
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
resolute
needs-triage
trusty
needs-triage
xenial
needs-triage
Red Hat logo
Red Hat Enterprise Linux Releases
Red Hat Product
Release
rsync
RHEL 9
0:3.2.7-1.el9_8
fixed
rsync-daemon
RHEL 9
0:3.2.7-1.el9_8
fixed
rsync-rrsync
RHEL 9
0:3.2.7-1.el9_8
fixed
Azure Linux logo
Azure Linux Releases
Azure Package
Release
rsync
Azure Linux 3.0
0:3.5.0-1.azl3
fixed
Common Weakness Enumeration
References
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0
https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635
https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header